how do I add a new disk to ZFS and make it available existing mountpoints if the current pool is root pool?

Question

My S11 server has the following configuration:

disk #1 is used for rpool, which is the root pool I want to add disk #2 to increase the size available for the already mounted folders, but I can't add the disk to the existing rpool because its the root-pool.

Is there a way to make the new disk available for the "/" folder? Is my only option to create a new zpool and mount it under a new folder?

Thanks.

RaamEE

---

 root@raamee:~# zpool status
  pool: rpool
 state: ONLINE
 status: The pool is formatted using an older on-disk format. The pool can
         still be used, but some features are unavailable.
 action: Upgrade the pool using 'zpool upgrade'. Once this is done, the
         pool will no longer be accessible on older software versions.
  scan: none requested
 config:

         NAME        STATE     READ WRITE CKSUM
         rpool       ONLINE       0     0     0
           c4t0d0s0  ONLINE       0     0     0

---

root@raamee:~# zfs list
NAME                       USED  AVAIL  REFER  MOUNTPOINT
rpool                      130G  4.18G  4.59M  /rpool
rpool/ROOT                 101G  4.18G    31K  legacy
rpool/ROOT/S11-GA          152M  4.18G  7.33G  /
rpool/ROOT/S11-GA/var     17.4M  4.18G  5.20G  /var
rpool/VARSHARE             180K  4.18G   180K  /var/share
rpool/dump                8.25G  4.43G  8.00G  -
rpool/guests                31K  4.18G    31K  /guests
rpool/scratch             2.52M  4.18G  2.52M  /scratch
rpool/swap                20.6G  4.81G  20.0G  -

---

root@raamee:~# format
Searching for disks...done


AVAILABLE DISK SELECTIONS:
       0. c4t0d0 <FUJITSU-MBB2147RCSUN146G-0505 cyl 17845 alt 2 hd 255 sec 63>
          /pci@7b,0/pci1022,7458@11/pci1000,3060@2/sd@0,0
          /dev/chassis/SYS/HD0/disk
       1. c4t1d0 <FUJITSU-MBB2147RCSUN146G-0505-136.73GB>
          /pci@7b,0/pci1022,7458@11/pci1000,3060@2/sd@1,0
          /dev/chassis/SYS/HD1/disk

Solution 1

Attach the second disk as a mirror of the first, wait for resilver, remove the first disk, set the properties to autoexpand. Don't forget to setup boot code or anything like that. Example:

zpool attach rpool olddisk newdisk
...wait, check using zpool status rpool
zpool detach rpool olddisk
zpool set autoexpand=on rpool

Solution 2

You cannot "expand" the rpool size by appending one disk to another (raid 0), as previously mentioned, however as Chris S mentioned below, you could attach a larger disk as a mirror, then, once the data is sync'd (resliver complete), detach the smaller disk. (oops now I see Chris's response too)

Here is a process to mirror the root disk... http://constantin.glez.de/blog/2011/03/how-set-zfs-root-pool-mirror-oracle-solaris-11-express

Follow that except that where they do:

prtvtoc /dev/rdsk/c7t0d0s0 | fmthard -s - /dev/rdsk/c7t1d0s0

... you will want to run format and make the size of slice 0 larger, probably the whole disk

# format /dev/rdsk/c4t1d0s0

(I will not go into great detail on the interactive format command)

# zpool attach rpool c4t0d0s0 c4t1d0s0

# zpool status rpool

WAIT UNTIL IT SAYS "resilver completed" (keep checking zpool status rpool)

MAKE SURE YOU CAN BOOT TO THE SECOND DISK

Then detach the smaller rpool mirror and reboot, make sure you can boot again.

# zpool detach rpool c4t0d0s0

PROFIT!?

REFERENCE: http://docs.oracle.com/cd/E19963-01/html/821-1448/gjtuk.html#gjtui

---

Previous Answer:

After creating the pool using the command he specified:

zpool create mypool c4t1d0

Create a filesystem, for example:

zfs create mypool/home

... copy the data to the new disk ... (re)move the data from rpool disk, then set the mountpoint to a proper location, such as:

zfs set mountpoint=/export/home mypool/home

That is, of course, assuming that /export/home is where all the space is being used. You may have to do this in "single user" mode, or create a user with a home directory that is not in /export/home to complete this.

On a side note, your zfs list output looks funky, like it is missing something. rpool/ROOT is showing 101GB used, but the filesystems under it are only showing about 12.5GB REF, and far less USED. Do you by chance have other boot environments under rpool/ROOT that you "trimmed out" of your zfs list output? could you maybe destroy those bootenv's or at least the zfs filesystems to regain the space used in rpool/ROOT?

~tommy

Solution 3

Yes, I believe your only option is to create a new pool using the second disk. The only thing you can do with the rpool is mirror the disk - which won't make more space available. The rpool doesn't support striping, due to the difficulties it would pose with booting.

zpool create mypool c4t1d0

Comments

[Philip]

Sorry to be pedantic, but you can create a mirror of the rpool with a larger disk, then remove the smaller disk, and grow the rpool - this effectively increases the size of the rpool, which your first sentence says is not possible.

[TommyTheKid]

Chris S: You are correct, I hadn't thought of that. You should post the "correct" answer ;)