June 16, 2025

How do you make a snapshot backup?

How do you make a snapshot backup?
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This episode breaks down snapshot backup fundamentals, covering the key differences between traditional storage snapshots and cloud-based approaches. Curtis and Prasanna explain copy-on-write versus redirect-on-write methods, performance implications, and why some snapshot systems can degrade performance by up to 50%.

Learn about NetApp's redirect-on-write innovation, VMware's unique approach, and how AWS "snapshots" are actually more like traditional backups. The hosts discuss critical concepts like read-only snapshot properties, storage space management, and the importance of copying snapshots to create true backups that follow the 3-2-1 rule.

Whether you're managing traditional storage arrays or cloud infrastructure, this episode provides practical guidance on turning snapshots into effective backup strategies. Topics include performance optimization, immutable storage considerations, and real-world implementation challenges that every IT professional faces.

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You found the backup wrap up your go-to podcast for all things

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backup recovery and cyber recovery.

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In this episode, we tackle a confusing phrase, snapshot backup.

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I know what you're thinking, Curtis.

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Isn't that an oxymoron?

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Well, that depends on what you mean by snapshot.

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We're gonna break down the difference between what I'm calling

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traditional storage snapshots and what vendors like AWS call snapshots.

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Which are actually more like backups.

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We'll talk about copy on write?

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Redirect on write.

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VMware snapshots that are just weird.

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How to turn your snapshots into actual backups that follow the 3, 2, 1 rule.

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Uh, pretty much everything that you need to know about making.

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A backup snapshot.

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If you don't know who I am, I'm w Curtis Preston, AKA, Mr.

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Backup, and I've been dealing with this topic for over 30 years, ever since.

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I had to tell my boss that there were no backups of the production

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database that we had just lost.

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I don't want that to happen to me.

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I don't want that to happen to you.

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That's why I do this.

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And so, enjoy this episode of the backup wrap up.

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Welcome to the show.

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Hi, I am w Curtis Preston, AKA, Mr. Backup, and I have with me my QOS advisor

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Prasanna Malaiyandi how's it going?

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Prasanna?

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I am good Curtis, and I'm glad that we don't have a random five second lag

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every time we talk, so That's good.

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Yeah.

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So, uh, we figured out, we, we were, we started to try to record this

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and there was this massive lag.

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Um, and, um, I realized that basically like I counted 'em real quick.

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There are four people currently watching Netflix.

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Uh, I was able to stop one of them, but I don't control the other ones.

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And so you came up with the idea of, you know, what about QOS?

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And so I, I have a firewall.

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Um, and, uh, so I, I enabled SmartQ, I put this website on it and I

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said, give me, gimme all the stuff.

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Gimme everything I can.

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And uh, so now it's, you know, beautiful.

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So I guess that's a plug for firewall as well, not a sponsor.

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Yep.

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Or for any router software that actually supports proper QOS, not like most

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Yeah.

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consumer level ones, which don't do a great job.

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Yeah, so this is, I I've been very happy with the, with

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the firewall since I got it.

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Uh, every once in a while I use something, you know, fancy on it when this is nice.

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So, um, so, um, we haven't recorded in a while.

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You, you went away.

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I went away.

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I went on vacation for the longest vacation I've been

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on in seven years I think.

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So I was gone out of the country for three weeks, which was nice.

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I was off in India for a wedding, visiting family.

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Lots of travel.

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So much good food.

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Curtis, um, and

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Yeah.

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I might be addicted to caffeine.

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So

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In India as you've had, right, uh, they serve in the south, they

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serve filter coffee, which is sort of a small cup of coffee, which

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is very, very concentrated though.

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And, uh, I was drinking three or four a day.

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Now this is normally someone who drinks maybe one cup of

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coffee a day, other than when

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Yeah.

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office where it's maybe two.

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So.

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Yeah.

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Yeah.

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Well anyway, well welcome back to the same time zone.

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Very excited.

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Thank you.

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but It is hard with the 12 and a half hour time zone difference.

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You know, it was like

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Yeah,

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we get a brief window to chit chat, or in the evenings we get a brief window to chit

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yeah, yeah.

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I basically wake up and call you and then before I go to bed, I call you.

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Right.

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Um, and, um, uh, yeah, so a lot of people don't know that it's,

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that it's 12 and a half hours time difference, which is just odd.

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yeah, I don't know why they do the half hour.

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Yeah, just funny.

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Maybe they, they saved the half hour to drink the filter coffee.

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So, uh, all right, well, today we're gonna talk about, uh, you know, and I

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thought, you know, you thought maybe we'd covered this already, or at least

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recently, and, and we really haven't.

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So this is a, a word that comes up a lot in, uh, in the show.

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And that is this word snapshot, which.

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If, if we, if we go outside of it, it, it, it means that, you

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know, it's, it's a picture, right?

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That that's what the word snapshot and also.

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There's another word that's gonna be used in this episode, which is image, which

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is really just another word for picture.

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But in our world, an image is very different than a snapshot.

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And as you've often heard me say, words mean things.

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And um, I want to make sure that this is sort of a, I'm gonna

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call it snapshots basic episode.

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So if you're, if you're just wondering what you know, what are snapshots, what

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are the different types of snapshots?

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Both what I'm gonna call the traditional snapshot, which is the ones that you and

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I, you know, grew up on, if you will, and then something that is relatively new.

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Again, comparatively speaking, new, uh, that is also being called

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snapshots, which is actually something completely different.

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So, um, uh, and then what purpose they serve, uh, et

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cetera, et cetera, et cetera.

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Any, any other sort of introductory things you can think of before we get started?

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no.

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I also did like your analogy of a snapshot is like a picture

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that you would take right

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Yeah.

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of like tech, right?

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And,

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Yeah.

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thing to add is that's important is it captures a moment in time.

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Yes.

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Right.

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A

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One moment in time.

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Sorry,

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and

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go ahead.

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but, so we're not referring to a video or whatever Apple calls

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their eight second or six second

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Yeah,

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that they send over.

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Right.

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That's not what we're referring to.

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It's a single

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Yeah.

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Yeah.

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So first let's talk about what I'm gonna call the traditional snapshot

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and, um, which I, another word, it's funny now that I think about it.

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This other word that I'm gonna use is also sort of like, um, it's

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also a word that is used outside.

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Id to also mean.

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You know, looking at a thing, right?

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And, uh, the word that I'm gonna use is view.

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Mm-hmm.

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So, uh, if anybody has any experience in databases.

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Right.

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There is this concept called a view, which is a different view into the database,

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which gives you, it looks different than, um, than the, the, the entire database.

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Right.

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It is a, it is a view, a a particular point of view, if

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you will, into the database.

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I don't want to go too much into that for two reasons.

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One is not really relevant.

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Two, I will probably mess up the description, but, um.

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Because it's one of those areas where it's right at the edge of my, of my experience.

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I am not a DBA, um, but I've often had to pretend to be one

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in order to back up databases.

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But this goes to your concept or your, the, the point that you were

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making is that a snapshot, uh, is a view of the storage at a particular

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point in time, so it is a view of your typically file system, but also

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it could just be a volume, right?

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A virtual volume at a particular point in time and what your, when

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you look at that snapshot, the actual blocks that you are looking at, or

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you're copying or you're accessing.

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What you are looking at.

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Is going to like where the blocks come from is going to be based on how the

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snapshot is actually being delivered.

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Sometimes you are going to be looking at the blocks from

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the original storage device.

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Sometimes you're going to be looking at blocks from some

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sort of cash snapshot area.

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Mm-hmm.

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Um, and so this view that you're looking at is this sort of virtual

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view of a particular point in time and it just keeps track of everything.

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And it says, okay, at this point in time they go to ask for this block.

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It knows what was where.

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So it goes, at this point in time, block A was.

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You know, at this status, well block A is still that status over on the original

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storage device, so we're gonna go get it.

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Or if you ask for block B, you go, block B was this status, and we can

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see that that status has changed.

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And so we're gonna get that block from the snapshot area.

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Um,

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And

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go ahead.

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does a different implementation.

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Yeah.

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think most of.

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As of what I know right now is they're all kind of, all the blocks

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are shared, and like you said, as things change, new copies are created

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that contain the updated version.

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But there's all this metadata and mapping, all this stuff is what

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the storage vendors, that's really like what they focus on, right?

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Is how do they make it fast?

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How do they make sure that you have that plausible point in time view to look at.

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Yeah.

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And, uh, we're gonna talk about, uh, like a couple of different

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ways that this actually happens.

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Uh, but the, but when you think about the way I described how that works,

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the important thing to understand is I said that if you grab blocks, one

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part of the, you know, one set of blocks where you're going to get those

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blocks from is from the original.

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Thing, right?

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The, the device, the volume, et cetera.

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And the other way is you're gonna get blocks from the snapshot area, but

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the, but the thing that you should infer from that is that in order for

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the snapshot to function, you need the original device to continue to be

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Mm-hmm.

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functional and et cetera, et cetera, et cetera.

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Yeah.

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Yeah.

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Um,

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thing to

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yeah.

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that's important for snapshots Curtis

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Mm-hmm.

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is that snapshots are read only, right?

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Which is a critical fundamental, uh, the, the property of a snapshot, right?

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Just like a

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Yes.

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you take a picture, you're not modifying that picture,

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Right.

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Good point, good point.

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Um, and because otherwise it wouldn't be a snapshot of that point in time.

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Now you can take a snapshot and you can make it read, right?

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But at that point, it's really no longer a snapshot, right?

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Um, it is a completely different sort of function.

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Yeah, and typically for those ones do have that snapshot, and then

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normally when you make it read, write, you're creating a new entity.

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So the snapshot still exists, but then the all the writes go

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Correct,

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entity.

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correct.

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Correct.

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Um, so there are.

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Two different ways that snapshots, again, traditional snapshots are typically done.

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And there's what I'm gonna call, um, sort of the the traditional Traditional, okay.

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And that is this concept.

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And this is pre NetApp, basically right before NetApp started doing snapshots.

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'cause NetApp really kind of reinvented snapshots and, and how they work, right?

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Before NetApp, you had what was called the copy on write Snapshot and where

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it gets, or CCOW copy on write Snapshot and where it gets that, that name is

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that you, you have a block, right?

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When, when you make the snapshot at the very beginning of making the snapshot,

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all blocks are in the original device.

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Because nothing has changed.

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The moment you go to do something, you go to update, you know, a block.

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The question is what happens now?

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So in a copy on write situation, the um.

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We're going to, before we change that block, we're going to copy that block out

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to the snapshot area so that later when we go to, um, access that block, we say, oh,

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we need the block from this point in time.

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That block, at that point in time, is only available over

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in the snapshot area, right.

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What's important to understand is that when you go to update a, a block

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with a copy on write, um, snapshot, it has to do a right of that block.

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It has to move the data, then copy, you know, write that.

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Old block in the snapshot area, and then it's gonna write the

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new version of that block.

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So there are three IO operations for every right operation

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in a copy on write snapshot.

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And then the more snapshots you have.

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And the more, and the longer you keep them, the more, uh, of your blocks

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that you're going to have to copy every time you, uh, write new data.

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Is that, how did I do with that explanation?

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yeah, you did.

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Well, um, the other thing also is at some point you end up with a

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Yeah.

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As well, just because of how writes are being done.

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And remember all the time, these aren't just small blocks, right?

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So even if you go modify, say a hundred bytes in a block, you still

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have to write that entire block back,

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Yeah.

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Yeah.

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sort of the underlying building block for the file system.

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And

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Right.

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this could lead to a lot of wasted reads and writes and IO that you're consuming.

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Are you, did you just say that the block is the basic building block?

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It is funny, the words that we use, right?

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Um, yeah.

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And so, um, what's it, I, I think one of the most important things to understand

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about a copy on write Snapshot set up is that over time, if you have a lot of

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snapshots and you keep those snapshots for a significant amount of time.

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The performance of your primary array because it's having to do all of this

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copying, you know, on, you know, on write.

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The performance of that, both the read performance and the, and

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especially the write performance can be significantly degraded over time.

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Yeah, and I'm just thinking, don't know any systems to my

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Mm-hmm.

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that still use copy on write.

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I am sure there are some, but I, but I would agree with you that

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most newer storage vendors realize sort of the evil of copy on write.

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You know, the, the, you know, it's, it's, I. It's, it's, it's sort of like

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the famous Maya Angelou quote, right?

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Like, we did what we did when we knew what we knew, but now we know

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different and we do different.

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Right?

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Uh, that's a, that's a massive, uh, I'm sure misquote of, but I think I

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got, I think I got the concept there.

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And I remember being at a large, very large oil and gas company

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and we were, um, you know.

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Helping them do a, it was an, it was a RFP, right?

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Um, for, for just a massive, uh, storage change.

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Right.

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And, um, they knew how many snapshots they wanted to create, and they knew

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how long they wanted to create them.

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They were already a, a NetApp customer.

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The, the problem with being a NetApp customer was they knew every.

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Bad thing about NetApp, right?

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They, they, they could see right through the stuff that they said that was bs.

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Right.

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You know, every vendor has got some amount of bs, but they were a customer,

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so they knew everything that NetApp, you know, they knew every blemish about

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NetApp, but they, and they were bringing in other vendors to see if perhaps they

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could get what they get from NetApp.

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Uh, while changing the vendor.

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And one of the things that they want is they wanted 90 days of user

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browsable snapshots, and they had all this data to show how much money

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that that was saving them because of the number of user generated

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restorers that were happening, right?

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Because one of the great things about having snapshots is that if you give

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them access, your users can just go to the right area and they can see their

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directory from a different point in time.

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Right?

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And so they, they had all this data that showed that they had all these user.

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Generated restores and um, uh, and so they said we want 90 days

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of user browsable snapshots.

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I won't name the vendor, but let's just say it's a fundamental law of physics.

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Um.

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That vendor said, uh, if you do that, you know, you're, you're, you're, 'cause

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they were, you know, they were doing copy on write snapshots at the time, and

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they basically said, you're going to have a significant performance degradation.

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And they, and they asked them like, how bad, and they just sort of, you know.

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Spitball the number, and they said it was 50%, like a 50% performance

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degradation, but they're like, we actually don't know because no one does

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that, no one does that with our storage.

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Right.

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Um, and, um, uh, yeah, so it's, it's a really big deal.

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Right.

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So that is,

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Yeah.

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I. Copy on.

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Right?

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Which is the old school way of doing snapshots.

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And if you're currently having any problems with your snapshots,

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maybe you investigate and see if they're copy on write?

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That's gonna be your core problem, right?

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Um, and, and it's gonna fall under the category of

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doctorate hurts when I do this.

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Well, don't do that.

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You need to do fewer snapshots or whatever.

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I just realized there is one vendor that still does copy on.

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write.

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And do you know what that is?

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Who?

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Microsoft with VSS Snapshots?

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VSS.

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The volume shadow services.

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Yeah.

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Yeah.

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Yeah.

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I was just thinking about that.

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I'm like, there has to be someone, and I was like, oh, yep.

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Yeah.

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And, and by the way, that brings up a, a really good, uh, thing that maybe

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we should have covered earlier on.

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And why do you, why do you make snapshots?

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Right?

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There's two reasons.

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And VSS is the second reason.

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The first reason is that it acts as sort of, kind of like a backup

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Mm-hmm.

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that it gives you this view, this place that you can go get and get the file

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the way it looked three weeks ago, three months ago, six months ago, whatever.

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However long you keep your snapshot.

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Go ahead.

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can we call it little B backup?

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Because, because here, here's my

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I what you're saying?

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Yeah.

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gets, because it doesn't follow the traditional

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Yeah.

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backup of 3, 2, 1 rule and everything

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Yeah, that's why I'm saying it's kind of like a backup, right?

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Yeah.

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Um, it, it's not really a backup until you copy that snapshot

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to some other location, right?

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So, and it also needs to be managed and all that kind of stuff,

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and you need to know what's in it and all that kind of thing.

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Anyway, but to, to follow the 3, 2, 1 rule, you need to at least

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copy it to another location.

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Hopefully that location is offsite and now we got three

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copies and two locations we got.

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Okay.

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So, um, actually, if all you're doing is.

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Snapshot of replication, you're actually not following 3, 2, 1 either because

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it's not, you don't follow the two, you don't have, you know, 'cause the two is

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meant to be two different risk profiles.

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And if you, if you go from one filer to another filer and you're, yeah.

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Okay.

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Um.

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The second reason that you make a snapshot and VSS falls under this

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typically, and that is what you're doing, is you're creating a stable

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point in time that is now read only that you can then use to back up.

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Mm-hmm.

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You can point your backup.

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And most backup vendors that are, that support windows, they integrate with VSS.

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And what VSS do?

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You, you, you talk to VSS and, , basically, you know, quick

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summary there, there's, there's this concept of a, of a VSS writer.

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You talk to the VSS and you say, Hey, I'm here to do a backup.

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What kind of, um, you know, what kind of stuff do you have?

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And they're like, we have SQL Server.

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You're like, okay, do a snapshot for SQL Server, and then you, and then

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that gives you a, a stable point in time to back up this, this device that

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otherwise is moving around, right?

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So it, it gives you a read.

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Only copy that isn't changing while you're backing it up.

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And then if you're just there to do a backup, it actually immediately

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deletes the snapshot as soon as you're done with the backup.

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Right.

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So that's the second reason that we use a, a snapshot, which is

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just to create a stable point in time from which we're gonna run.

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I'll call it a big B backup to use your, to use your, your terminology.

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All right.

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So that's copy on write?

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Uh, do you wanna describe, redirect on write.

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Yeah.

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So this is basically what NetApp does

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Yeah.

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Although they would say no 'cause they say there's a slightly

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different, but that's okay.

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You know?

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Yeah.

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NetApp is probably most famous for this with its write anywhere file layout

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Yeah.

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right?

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Which basically says when you're going to actually do your writes, you don't

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need to overwrite the existing block.

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Right.

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gonna pick any other random block, and then you're just

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gonna keep track of where it is.

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So all new writes go to all new blocks, so you don't have to ever

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worry about going and updating all the metadata and copying data out, and so

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you're efficient in your write code.

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Pap and managing snapshots becomes a lot easier.

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And so the where the term redirect on write, is instead of overriding the

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block in its current location, you're just gonna redirect that, write?

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Put it in another location, and then your snapshot manager just needs to keep

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track of where the old location was.

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So the big difference between a redirect on write, so there's a,

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there's a plus and minus here.

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The plus is much better performance,

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Yep.

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right?

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Which is why.

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Pretty much most vendors have gone with that as the newer.

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Um, the downside is snapshot data and production data all

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in the same volume, right?

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There's no snapshot area.

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It's, it's everything.

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So if you keep snapshots too long, you can actually fill up your, your

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volume, um, and have a problem.

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Yeah.

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And they, that's why they do try to do things like setting up a

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snapshot reserve space so you can automatically start deleting it

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once it gets to certain too high.

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But yeah, there are cases where that could also still be problematic.

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So,

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Yeah.

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And, and this is why, because you can do snapshots essentially.

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With impunity, you can do as many snapshots as you want, as often

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as you want, without, um, and, and keeping them as long as you

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want without any zero performance.

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Issues as long as you keep enough storage around for your snapshots, right?

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Uh, 'cause then we start getting low on blocks and we start, you know,

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then we, that, that, that, that, that's a totally different problem.

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So as long as you have enough space for your, uh, for everything,

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then you shouldn't have any performance from redirect on write?

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Snapshots.

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Yep.

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And I think with it now, I think the latest NetApp snapshot limit

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is I think a thousand snapshots.

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It used to be 2 55 for a while, but

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Yeah, the,

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a

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the famous 2 55 and yeah.

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Yep.

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It's funny how that number just sort of, well, 2 56 really is the number,

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but 2 55 is, we can't do 2 56.

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We can do two.

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Well, it's 2 55 because active is always zero.

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Oh, there you go.

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There you go.

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Yeah.

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Yeah.

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Um, so that's redirect on write.

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And that, you know, and we, we really talked about it very quickly, but

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basically it means that you can have as many snapshots as you want, as long as you

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want without any performance degradation.

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So that's generally what you find in most common, uh, snapshot providers right now.

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other thing I wanna also mention, copy on write?

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Versus redirect on write.

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Mm-hmm.

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discs, it made a huge benefit For Flash.

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It makes an even bigger impact with Flash there are issues around

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right amplifications when you're

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Mm-hmm.

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um, as well as how many wear cycles you can have on your flash.

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And so redirect on write is actually much better, both from a performance

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and longevity perspective for Flash

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Right.

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was on disc.

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So

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So the prob the problem there is that you're worried that you're having

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too many writes to one cell, and each individual cell in, um, flash has.

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A limited number of times that it can be overwritten, right?

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And so the worry that you have is if you have too many writes to the same block,

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you actually end, uh, to the same cell.

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You actually end up, that cell can become, uh, no longer usable

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but basically each cell has a finite number of times that you

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can overwrite that cell and you hit that and that cell is done.

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And now you know, it's like a bad block on a, or a bad sector on a disc, and

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you gotta move on to the next sector.

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and, and one other thing to mention too is I know so far when we talk about

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writes, people are probably thinking, oh, you're just writing a block of data.

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But remember with that block, you have a bunch of metadata

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associated with it, right?

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Indirect blocks that point to other blocks that contain metadata and everything else.

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That all needs to be updated by a file system.

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So even just doing like a hundred byte right,

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Mm-hmm.

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require, say.

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20 other blocks to be updated as

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Right, right.

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Exactly.

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Yeah.

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So those, so those are the two sort of what I'd call traditional snapshots.

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Right.

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Um, and now, and the second one is now what I would call

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sort of the standard snapshot.

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yeah.

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is a third.

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Really weird way that his snapshots are done, which I'm

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just gonna cover really quick.

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And that is VMware.

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So they do a, um, I, I believe it's a copy on write, but what's real

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actually, actually they do a, I'm gonna call it a weird on write?

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So what they do when you write a new block.

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They don't write the block to the, and and by the way, this is my understanding

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of the way VMware's, um, snapshots work.

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If I am now wrong, please tell me, but this is, I've checked repeatedly and this.

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I believe is still the case.

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So what would happen is when you take a snapshot in VMware, usually for backup

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purposes, um, when you go to write a new block in VMware, it doesn't write

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the new block in the production area.

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It writes the new block over in the snapshot area, leaves the

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original version of the block on the disc, and then it stays that way.

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Until you delete the snapshot, in which case it updates all the blocks to the new,

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Yep.

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thing.

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And, and, which is why, and, and I, I administered VMware for, for

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a while at least not really in a production environment, but, but

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you know, in a lab for a while before I realized this was the case.

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And so it means, what that really means in practice is you really can't use.

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At all.

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You can't use VMware snapshots the way you can use NetApp snapshots

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or even copy on write snapshots because the performance is way worse.

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Right.

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Uh, at some point you go to delete snapshots and you think deleting

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snapshots would be a nice thing, except when you delete the snapshot, there's

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this flurry of IO activity to update the primary volume with any of those blocks

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that are now the, the current block.

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It's the messiest thing I've ever seen.

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So two things to add.

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One is for VMware, it's okay if you keep those snapshots around.

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For a short duration.

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For a short duration.

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Yeah.

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for a short

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Yeah.

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it's fine, but don't think about using it for like that 90 day user restore use

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Mm-hmm.

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that you were mentioning earlier,

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it for a day or so.

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Right.

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And then delete it.

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Right.

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Make that a normal part of your thing.

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Exactly.

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And then the second point is with all of these snapshots, VSS VMware, most

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of them support two modes of operation.

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One is sort of a software based snapshot approach where they're

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dealing with all of this.

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So like Curtis mentioned with VMware, right?

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They're keeping track of everything.

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The second thing, second way that they also support it, is they

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integrate with the storage vendors.

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So when you go say VMware, go take a snapshot.

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VMware will do some things and then it'll call into the underlying storage

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provider and say, okay, now go do a hardware snapshot and lock in that data.

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In which case then you don't have all of these issues that Curtis just

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Exactly.

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That's a really good point.

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Thanks for, uh, bringing that up.

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Right.

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So VSS and VMware and maybe other sort of software level snapshots, they

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do have this concept of talking to a storage array and then putting that

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storage array, making, making, letting the storage array do the hard work.

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Right.

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Which is, which is.

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I, I think certainly the preferred way to do snapshots is to do it in, in hardware.

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Yeah.

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. So the final way of snapshots, and this is the snapshots that most of you

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know, because most of you are very, you are your head's in the clouds, right?

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And that is, and, and I'm, I blame Jeff Bezos, um, because it

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was Amazon, I believe that first started using the term snapshot.

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To actually refer to something completely different.

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If you go into a, you know, if you go to a number, it used to just be

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like EBS, the Elastic Block storage.

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Right.

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Um, that, or you take, uh, a snapshot of a EC2 E image.

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Yeah.

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RDS Right.

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You know.

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If you take a snapshot, as I made quotes in the air, it doesn't do

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anything like what we just said.

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It creates what I would call an image copy, right?

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Of that thing that you just took a snapshot of and it creates a

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basically bite for bite copy of that.

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And typically, I think it's, I'll just speak in terms of a, you know, AWS,

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it creates that bite for bite copy in.

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S3, right?

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It stores it in a special reserve area in S3, and so when you create a snapshot

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in pretty much anything in Amazon, what you're actually creating is a backup.

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You're creating an image copy of that device.

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You're putting it in S3.

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Um, you can even, um, you can often specify where an S3, right, so you

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can specify that you want that backup to go to another region, for example.

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Um, and you can also copy these snapshots around, um, and, um, yeah,

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But you can't access it directly via S3,

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correct, correct.

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Like, yeah, that's why I was saying it's like a special, like reserve area.

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NS three.

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Yeah.

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it's

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That's for, that's for a lot of safe safety reasons, right?

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Yeah.

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It's called a snapshot, but it honors a lot of our backup

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with a big B requirements.

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Yeah, because it's an actual copy, you can specify that it be sent to a, to

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another region, to another account.

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Right?

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And that's what I wanted.

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I want it in another account.

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I want it in another region.

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I don't want you to just do an EBS snapshot, for example, to the

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same availability zone, uh, that.

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Isn't, doesn't really follow the basic 3, 2, 1 rule, which is

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something we talk about a lot.

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Yeah.

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But I do, I do think it's important to understand that a snapshot in,

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in A AWS is so much, most, so much closer to what I would call a backup.

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In fact, depending on how you do it, it definitely is a backup

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than what we typically talk about when we say snapshots.

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Right.

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And, and it's interesting because there are vendors that have made

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a, a deal of, you know, they're like snapshots are not backup.

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And they've been saying that for so long that they continue to say that.

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When what we're really talking about is AWS when it really is

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a snap, it really is a backup.

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it's interesting you bring this point up because think other vendors, other

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traditional storage vendors are also now starting to go the same route

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where they're saying our snapshots can now be offloaded into object storage.

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Right.

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Yes.

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I, yeah, I have seen some of the, some vendors do that.

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Yeah.

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Right, which is very similar to what AWS has been doing, but I think

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they still call them snapshots.

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Right?

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So

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Yeah.

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of this, you have to, I think it's important as administrator, an IT

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person to really ask the question.

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When someone says snapshot, what do they mean?

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Yeah.

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Right.

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I'm gonna, and we had, we used the phrase snapshot backup in this,

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um, in the title of this episode.

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And this is a snapshot backup, right?

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So it, it's some would see snapshot backup as like a, like a oxymoron,

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like, like military intelligence, you know, um, that, you know,

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two words that can't go together.

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But if by snapshot you mean what they do in AWS and I. Similar, uh,

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you know, other cloud vendors, then I'm fine with calling that a backup.

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Just make sure, so the question is, how do you make a snapshot backup?

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Well, there's two ways.

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One is if you're talking the traditional type of, you know, storage snapshots,

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you need to copy that snapshot to another, uh, storage array.

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Hopefully one that's offsite.

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Um, hopefully one, you know, my dream would be.

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Is to another vendor or you, then you, you, you change the

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form of the snapshot, right?

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You know, you're doing, you're doing, you know, filer to filer and then you're,

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you're backing that up to some other, uh.

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Object store

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system, right?

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Yeah.

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might do NDMP, who, you know somewhere, uh, Steven, uh,

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his, his ears are perking up.

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Um, the, um, uh, anyway, but if it's, but if it's, if it's a cloud vendor,

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typically, and again, I can really only speak with, with authority and

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AWS, but from what I've seen, the other cloud vendors are very similar.

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When you take a snapshot in AWS, you're actually taking a backup.

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And when you're doing that.

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You can use AWS backup to sort of control all of this, which is AWS backup is

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really just a control plane for all the other stuff that's going on, and

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you can make sure that you know that you're following the 3, 2, 1 rules.

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You have a different account, different availability zone, different region even.

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Um, yes, it makes it cost more, but it actually makes it a real backup.

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So, questions for you.

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Yeah.

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So you mentioned that sort of doing snapshots, replicating it from

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one filer to another filer doesn't quite meet the rules of the two.

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Right?

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In 3, 2, 1, backup.

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Uh, in the 3, 2, 1 rule.

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What if so many of these vendors now allow you to run virtualized

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instances in public clouds?

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Mm-hmm.

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So I could run a NetApp instance in AWS

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Yeah.

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My answer is no.

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I.

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because it's still the same software version.

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Yeah.

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Okay.

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Yeah.

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Now AWS

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it's better.

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Better, you know, good, better, best.

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It's better than the other thing because at least it

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isolates you from the hardware.

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But it's still, the os still the same os.

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And would you also consider the same like AWS offers file systems, right?

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So they have like support for NetApp by FSX.

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Would you consider replicate if it's, I'm not even sure

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Yeah, I don't, I don't know.

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I don't know if I can speak to that.

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Right.

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I don't know if I can speak to that.

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Right.

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And then, and then

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do you have to be for the two is my question.

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I, I, again, you're, you're just trying to, it, it's sort of a

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good, better, best thing, right?

Speaker:

The, the, the more different you can be, the better you are.

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It's difficult in this cloud world, right.

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Um, the, um, and some would say, well, isn't a w aren't AWS snapshots the same?

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And it's like.

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They're actually a little bit different because it is a full image

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copy, um, and it's stored in S3.

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If something were to happen to your EBS volume because of a bug in EBS,

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you could still use that snapshot, which is stored in a completely

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different system, which wouldn't have the same bug and store that in.

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You could restore that into EBS.

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that your volume wasn't corrupted by some EBS bug

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Well, but you're, but S3 isn't EBS.

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no.

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But when

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Oh, you mean, you mean before?

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Well, if it was created, if it was created, if it was corrupted

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by the EBSB, then you know Yeah.

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You're, that's gonna happen no matter what you do.

Speaker:

So, so the I, I like where you're going, Curtis.

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I think there's also sort of the practicality aspect that we have to

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also look out for, because ideally, like you said, right vendor, you

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have multiple vendors, right?

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You're using different technologies, but then you have to balance that with

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pr, sort of the practicality, right?

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Are you gonna be able to understand all these various technologies,

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build out the skillsets, integrate it, pay for it, right?

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We all know how small backup budgets are versus production budgets.

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Yeah.

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Yeah, yeah,

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just.

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And, and I've always tried, you know, throughout my career to try to be.

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To say, look, if you're asking me my opinion, you know I'm

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giving, I'm giving you the bar.

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Right, right.

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And you know, and I understand that people have to, they have to, they have

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to live in the real world where, where backup is not the most important thing.

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Ah, it hurts me to say that.

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Um, right.

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Um,

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but at the same time, maybe there are certain use cases where

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you can focus on it because of the high value of the data or

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Yeah.

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like that, where it is important to have

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Yeah,

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type solution.

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also want to add, you know, we talk a lot about the 3, 2, 1 rule, and I

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say that because the 3, 2, 1, like if it doesn't follow the 3, 2, 1 rule

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and it's just not a backup, right?

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I'll say the number one.

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Number two, I think I'd be remiss to say that also I. You know,

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we're starting to talk about things like the 3, 3, 2, 1, 1 0.

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You know, you do want at least one of your backups, your copies

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to be on immutable storage.

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Right.

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To be on truly immutable storage.

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One that even you can't delete even if you want to.

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Right.

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Um, because only then is that backup, uh, protected against a ransomware attack.

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Yeah.

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Or a, or a, or a direct bad actor.

Speaker:

You know, a, um, what's the, what do, what do we call it?

Speaker:

Um.

Speaker:

threat.

Speaker:

Thank you.

Speaker:

You know?

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No, there's a. Uh, uh, a rogue admin, right?

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Uh, you know, a rogue admin, either a rogue admin, right?

Speaker:

'cause there have been rogue admin stories, you know, uh, but also someone

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who is able to gain access to your administrative account and then go

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and delete all your backups you need.

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Only if even you can't delete it, even if you want to, is a backup, truly immutable.

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Um, and so you can do that with snapshots.

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You just need to copy them into something else.

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Yeah.

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All right.

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This was fun.

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Yay.

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Welcome back, Curtis.

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Yeah.

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And our, our lag wasn't too bad on our thing.

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Hopefully our QOS did its job and hopefully our recording, uh, works.

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And with that, that is a wrap.