Tuesday, May 6, 2008

ZFS Command Sheet For Solaris Unix 10 - Pool And File System Creation

Hey There,

Today, we're going back to the Solaris 10 Unix well and slapping together a few useful commands (or, at least, a few commands that you'll probably use a lot ;). We've already covered ZFS, and Solaris 10 zones, in our previous posts on creating storage pools for ZFS and patching Solaris 10 Unix zones, but those were more specific, while this post is meant to be a little quick-stop command repository (and only part one, today). This series also is going to focus more on ZFS and less on the "zone" aspect of the Solaris 10 OS.

Apologies if the explanations aren't as long as my normal posts are. ...Then again, some of you may be thanking me for the very same thing ;)

So, without further ado, some Solaris 10-specific commands that will hopefully help you in a pinch :) Note that for all commands where I specify a virtual device or storage pool, you can get a full listing of all available devices/pools by "not specifying" any storage pool. I'm just trying to keep the output to the point so this doesn't get out of hand.

Today we're going to take storage pools and ZFS file systems and look at creation-based commands, tomorrow we'll look at maintenance/usage commands, and then we'll dig on destructive commands and cleaning up the mess :)

1. To create virtual devices (vdevs), which can, technically, be virtual (disk made from a part, or parts, of real disk) or "real" disk if you have it available to you, you can do this:

host # mkfile 1g vdev1 vdev2 vdev3
host # # ls -l vdev[123]
-rw------T 1 root root 1073741824 May 5 09:47 vdev1
-rw------T 1 root root 1073741824 May 5 09:47 vdev2
-rw------T 1 root root 1073741824 May 5 09:48 vdev3

2. To create a storage pool, and check it out, you can do the following:

# zpool create zvdevs /vdev1 /vdev2 /vdev3
# zpool list zvdevs
<--- Don't specify the name of the pool if you want to get a listing of all storage pools!
zvdevs 2.98G 90K 2.98G 0% ONLINE -

3. If you want to create a mirror of two vdev's of different size, this can be done, but you'll be stuck with the smallest possible mirror (as it would be physically impossible to put more information on one disk that it can contain. That seems like common sense ;)

host # zpool create -f vzdevs mirror /vdev1 /smaller_vdev <--- The mirrored storage pool will be the size of the "smaller_vdev"

4. If you want to create a mirror, with all the disks (or vdevs) the same size (like they should be :), you can do it like this:

host # zpool create zvdevs mirror /vdev1 /vdev2 /vdev3 /vdevn... <--- I haven't hit the max yet, but I know you can create a "lot" of mirrors in the same set. Of course, you'd be wasting a lot of disk and it would probably make data access slower...

# zpool list
myzfs 95.5M 112K 95.4M 0% ONLINE -
host # zpool status -v zvdevs
pool: zvdevs
state: ONLINE
scrub: none requested

zvdevs ONLINE 0 0 0
mirror ONLINE 0 0 0
/vdev1 ONLINE 0 0 0
/vdev2 ONLINE 0 0 0
/vdev3 ONLINE 0 0 0

errors: No known data errors

5. You can create new directories, add file systems on them and mount them in your storage pool very easily. All you need to do is "create" them with the "zfs" command. Three tasks in one! (as easy as creating a pool with the zpool command):

host # zfs create zvdevs/vusers
host # df -h zvdevs/vusers
Filesystem size used avail capacity Mounted on
zvdevs/vusers 984M 24K 984M 1% /zvdevs/vusers

6. If you need to create additional ZFS file systems, the command is the same, just lather rinse and repeat ;)

host # zfs create zvdevs/vusers2
host # zfs create zvdevs/vusers3
host # zfs list |grep zvdevs
zvdevs 182K 984M 27.5K /zvdevs
zvdevs/vusers 24.5K 984M 24.5K /zvdevs/vusers
zvdevs/vusers2 24.5K 984M 24.5K /zvdevs/vusers2
zvdevs/vusers3 24.5K 984M 24.5K /zvdevs/vusers3

See you tomorrow, for more fun with Solaris 10 ZFS/Storage Pool maintenance/usage commands :)


, Mike