Slideshow explaining VDev, zpool, ZIL and L2ARC for noobs!

[danb35]

Even for a home user, though, the ability to have all your storage in a single pool (which you can expand as necessary) is beneficial. You don't have to worry about partitioning for particular types of data, hoping you've allocated enough room in a given slice, etc. It's just there. You can set a size limit on a dataset if you want, but you can also adjust that at any time in the future if you want or need to.

 

[avpullano]

ZFS isn't for small fries. You go with ZFS and you are definitely going to spend some cash, and you are certainly in it for the long haul. ;)

I'm certainly ok with that. After a couple of USB HDD failures, I've learned that protecting my data is worth investing in :D.

 

[ser_rhaegar]

VDevs help handle problems that are inherent with very very large servers. Even with RAID6 most hardware RAID controllers recommend against more than 10 disks in the same array. So if you had 30 disks and you followed the recommendations of hardware RAID you'd have 3 arrays. But on ZFS you could still have 1 large pool. VDevs actually free you from many limitations and are not a limitation in and of themselves.

Essentially multi vdev raidz2 is like raid60.

 

[ulua]

cyberjock,

Thanks for the info, this is good stuff, I have a lot to learn about FreeNas.
I will read this a few more times to make sure I understand everything.

Thanks,
ulua

 

[Market Guru]

thank you cyberjock, i just finished your power point. it was very informative. I will continue to read more of your guides before making decision on my NAS

 

[paulk]

I recently read through the presentation. Thank you for putting it together. It is very informative. Now I will hopefully configure my first FreeNAS correctly and avoid any catastrophes.

Here are a few minor corrections:

1. Slide 21 - should be titled Example 4, not Example 3
2. Slide 27 - should be titled Example 6, because it is a continuation of Example 6 from the previous slide
3. Slide 45 - you have an extra "only"
4. Slide 47 - 6th bullet has missing text

Perhaps it would be easier if you don't number the examples, because it is error prone and adds an unnecessary burden when updating the slide deck. Instead you could use descriptive titles (like in slide 28).

 

[cyberjock]

Yeah, I got those on my "to fix" list. I actually have a revision that I haven't posted yet with that stuff fixed.. perhaps I should update my links.

 

[R Bauer]

Thank you, cyberjock, for taking the time to put together that presentation. Well done, and very helpful!

 

[msbxa]

Very much appreciated for this guide. I would like to add something I think it's missing in the guide and would give extra bonus for all of us. Backup/Restore process for the most important things like zpool and FreeNAS boot OS or any other things to do or not do.

 

[Theodoros]

Just wanted to say thanks to cyberjock for his time and effort creating this slideshow. Very informative and easy to follow.

 

[GrahamBB]

Yeah, I got those on my "to fix" list. I actually have a revision that I haven't posted yet with that stuff fixed.. perhaps I should update my links.

Is there any significant change with the new release of FreeNAS?

Thanks for the guide, great study material!

 

[Ericloewe]

Is there any significant change with the new release of FreeNAS?

Thanks for the guide, great study material!

Not really, besides the boot device using ZFS, which allows for mirrored devices. That and UFS support being dropped.

 

[GrahamBB]

Not really, besides the boot device using ZFS, which allows for mirrored devices. That and UFS support being dropped.

Thanks!

 

[spchtr]

ANd I have no clue what you are talking about as vdevs have no "detaching" button. Disks themselves have a detach button. And if you don't have enough redundancy to support the vdev operating with that disk removed it will return an error that you cannot remove it from the pool.

Not sure what you are talking about, but vdev is not disk unless you are doing single disk vdevs. ANd in that case a detach button will exist but if you try to use it it won't work.

Actually I know this one. It's a command line for >zpool detach, you can do it to a physical drive of a mirror set vdev. It's used to detach half of a mirror, and returning the vdev to a single drive stripe vdev.

http://docs.oracle.com/cd/E19120-01/open.solaris/817-2271/gcfhe/index.html

It's at the bottom of that page.

Though I'm not sure why one would want to return to a single striped drive vdev, unless plans are to end up destroying the zpool to use the disks in a new one.

An example would be expanding your storage incrementally, but you'd want to take it out of production.

Start with a 6 disk Z2
Fill zpool

create 2nd zpool
add 2 disks
attach 2 disk Mirrored,
Fill zpool
add 2 disks
attach 2 disk Mirrored,
Fill zpool
Add 2 disk partitioned to 50%each
loose redundancy during next step (freak out)
detach 1disk first Mirrored
detach 1disk second Mirrored
partition and add 2 disks just removed
create 3rd zpool using 2nd partition of each partitioned drive
backup 2nd zpool to 3rd zpool.
Destroy 2nd zpool
partition and add 2 disk just removed
create 4th zpool Z2 with 1st partiton of 6 drives, or attach as 2nd vdev to 1st zpool
Backup 3rd zpool to 4th zpool.
Destroy 3rd zpool
delete 2nd partition of 6 drives.
expand 1st partition of 6 drives.
expand 4th zpool or expand 2nd vdev of 1st zpool.

I'm still trying to figure out a way to do this without taking the system out of production for the couple of days this is going to take with the large hard drives available these days. I'd also like to figure out a way to do this without losing redundancy, and on the fly in the background. I'd only do this on a home server with very limited user access used to store unimportant data like DVD/Blueray movie backups where I don't mind it being down a couple of days for maintainance.

Actually I'd probably try to plan better and just add the new 6 disk vdev to the 1st zpool once I'd bought all the drives if I could.

 

[Placebo]

A very well put together presentation. The animations didn't work for me though. Not sure if the problem is on my end.

I had a few thoughts:

After reading the entire presentation, I realize now that there are soooo many ways to lose your data.
It almost sounds like the presentation is trying to talk people out of ZFS. Of course, we both know better.
It might be worthwhile toward the end to add 1 to 3 additional slides highlighting why ZFS kicks so much a$$. ;)

For people on a tight budged, maybe suggest purchasing a single 8 gig rather than 2x4 gig sticks for their initial build.
Then they can easily upgrade if they plan to add more RAM down the road.

Anyway, a great presentation regardless!

 

[NiKiLLst]

First of all, thanks. I really appreciated your work.
Thanks, REALLY.

You made me think about going with FreeNas or not.
(Wanted to use FreeNas on a VM, I'm studying documentation you linked)

Great work, thank you once more for your effort!

 

[jmterry]

First Post. Thanks Cyberjock for putting the slideshow together. You mentioned that you were running a reactor before you were old enough to drink. Navy? I too was a nuke once!

I am still in research mode before I purchase components to build a system. In the interim I'm playing with OMV and setting up the plugins that I will eventually use in FreeNAS in jails.

Thanks for the work and commitment to the community!

 

[CLEAR RTC]

Thanks for the detailed slide show. It definitely cleared a few things up for me as well as giving me a good idea of what I really don't know, which is considerably more than I know. lol

 

[cyberjock]

Thanks for the detailed slide show. It definitely cleared a few things up for me as well as giving me a good idea of what I really don't know, which is considerably more than I know. lol

That is a very wise statement. Realizing you know far less than you don't know is a very good way to start. It's the people that think they know what they need and go off doing things that they don't know they shouldn't do are the ones that end up unhappy and often lose data. ;)

 

[3674578]

GREAT help for rookies. This document is very helpful.