Here is another HowTo, but this time its on ZFS. The ZFS file system is a revolutionary new file system that was developed by SUN. I have to say ZFS is awesome and very easy to administer, I've been pissed off lately with things that I can not do on OpenSolaris/SolarisExpress or things that take way to much time to do on Solaris. One thing that has been extremely easy to implement and administer has been ZFS.

Here I will explain the many benefits of ZFS below..

• ZFS is a transactional file system, which means that the file system state is always consistent on disk.
• All data and meta data is checksummed using a user-selectable algorithm. 
• No silent data corruption ever: ZFS self healing features automatically repairs corrupt data
• ZFS supports storage pools with varying levels of data redundancy, including mirroring and a variation on RAID-5
• The ZFS file system itself is 128-bit, allowing for 256 quadrillion zettabytes of storage
• ZFS supports SnapShots
• ACL Support
• many more......

 You will need Solaris Express nv80 or newer or OpenSolaris 2008.05

1. df -h    { See what devices are being used }
   
   

   -bash-3.2# df -h
   Filesystem             size   used  avail capacity  Mounted on
   /dev/dsk/c0d0s0        7.6G   5.4G   2.1G    72%    /
   /devices                 0K     0K     0K     0%    /devices
   /dev                     0K     0K     0K     0%    /dev
   ctfs                     0K     0K     0K     0%    /system/contract
   proc                     0K     0K     0K     0%    /proc
   mnttab                   0K     0K     0K     0%    /etc/mnttab
   swap                   1.0G   996K   1.0G     1%    /etc/svc/volatile
   objfs                    0K     0K     0K     0%    /system/object
   sharefs                  0K     0K     0K     0%    /etc/dfs/sharetab
   /usr/lib/libc/libc_hwcap3.so.1
                          7.6G   5.4G   2.1G    72%    /lib/libc.so.
   fd                       0K     0K     0K     0%    /dev/fd
   swap                   1.0G    48K   1.0G     1%    /tmp
   swap                   1.0G    44K   1.0G     1%    /var/run
   /dev/dsk/c0d0s7        7.6G    37M   7.5G     1%    /export/home
   
   

2. format   ( See what disks are available to us }
   

   -bash-3.2# format
   Searching for disks...done
   AVAILABLE DISK SELECTIONS
          0. c0d0 <DEFAULT cyl 2085 alt 2 hd 255 sec 63>
             /pci@0,0/pci-ide@1,1/ide@0/cmdk@0,0
          1. c0d1 <DEFAULT cyl 1021 alt 2 hd 128 sec 32>
             /pci@0,0/pci-ide@1,1/ide@0/cmdk@1,0
          2. c1d1 <DEFAULT cyl 1021 alt 2 hd 128 sec 32>
             /pci@0,0/pci-ide@1,1/ide@1/cmdk@1,0
    Specify disk (enter its number):

3. As you can see we have 2 disks ( c0d1and c1d1 ) available to use. So now we can create our zpool.
   zpool create linuxdynasty c0d1 c1d1
   

   -bash-3.2# zpool create linuxdynasty c0d1 c1d2

4. Lets check the status of our newly create pool.
   zpool status
   
   

   -bash-3.2# zpool status
   pool: linuxdynasty
   state: ONLINE
   scrub: none requested
   config:
   NAME        STATE     READ WRITE CKSUM
   linuxdynasty  ONLINE       0     0     0
   c0d1      ONLINE       0     0     0
   c1d1      ONLINE       0     0     0
   
   errors: No known data errors

5. We know we only have one pool but if you wanted to see the status of all of your zpools this is how you do it.
   zpool list
   

   -bash-3.2# zpool list
   NAME           SIZE   USED  AVAIL    CAP  HEALTH  ALTROOT
   linuxdynasty  3.97G   220K  3.97G     0%  ONLINE  -

6. zfs create linuxdynasty/opt   { Here we created the /linuxdynasty/opt file system, as you will see ZFS will automatically mount it for you as well }
   

   -bash-3.2# zfs create linuxdynasty/opt         
   

7. Now I want to make my /opt directory into a ZFS managed filesystem. In order to do this I will have to move the contents of /opt into /linuxdynasty/opt.
   

   -bash-3.2# mv /opt /linuxdynasty/opt

8. Remove the origianl /opt dir
   

   -bash-3.2# rm -rf /opt

9. Now we need to tell ZFS to change where the /linuxdynasty/opt points to in the file system.
   

   -bash-3.2# zfs set mountpoint=/opt linuxdynasty/opt

10. What if you do not want the /opt file system to grow out of control?? Well ZFS also can handle that by setting a quota on the file system as well
    

    -bash-3.2# zfs set quota=1G linuxdynasty/opt 
    

11. Now you can run a df -h,and as you can see all the mounting is done for you.. Now when you reboot the box all of your ZFS mounts will mount up automatically with out you having to modify /etc/vfstab since ZFS takes care of this for you.
    

    bash-3.2$ df -h
    
    Filesystem             size   used  avail capacity  Mounted on
    /dev/dsk/c0d0s0        7.6G   4.9G   2.6G    66%    /
    /devices                 0K     0K     0K     0%    /devices
    /dev                     0K     0K     0K     0%    /dev
    ctfs                     0K     0K     0K     0%    /system/contract
    proc                     0K     0K     0K     0%    /proc
    mnttab                   0K     0K     0K     0%    /etc/mnttab
    swap                   986M   1.0M   985M     1%    /etc/svc/volatile
    objfs                    0K     0K     0K     0%    /system/object
    sharefs                  0K     0K     0K     0%    /etc/dfs/sharetab
    /usr/lib/libc/libc_hwcap3.so.1
                           7.6G   4.9G   2.6G    66%    /lib/libc.so.1
    fd                       0K     0K     0K     0%    /dev/fd
    swap                   985M    48K   985M     1%    /tmp
    swap                   985M    44K   985M     1%    /var/run
    /dev/dsk/c0d0s7        7.6G    54M   7.5G     1%    /export/home
    linuxdynasty           3.9G    20K   3.4G     1%    /linuxdynasty
    linuxdynasty/opt       1.0G   543M   481M    53%    /opt
    
    

Now there is alot more that ZFS can do so If you want to see more please let me know and I will be more then happy to create more tutorials based on ZFS.