Installing "ZFS on Linux" on CentOS 6.3 with DKMS and L2ARC Caching

Prepare the system with the following packages,

yum groupinstall "Development Tools" 

yum install kernel-devel zlib-devel libuuid-devel libblkid-devel libselinux-devel e2fsprogs-devel lsscsi parted lsscsi nano mdadm bc 

Obtain the latest DKMS RPM package from Dell. Note that you need the latest version 2.x above for the installation to proceed properly.

wget http://linux.dell.com/dkms/permalink/dkms-2.2.0.3-1.noarch.rpm

Install the RPM package,

rpm -Uvh dkms-2.2.0.3-1.noarch.rpm

Obtain the latest version of DKMS RPM modules for SPL and ZFS,

wget http://github.com/downloads/zfsonlinux/spl/spl-modules-dkms-0.6.0-rc11.noarch.rpm

wget http://github.com/downloads/zfsonlinux/zfs/zfs-modules-dkms-0.6.0-rc11.noarch.rpm

Install SPL module first,

rpm -Uvh  spl-modules-dkms-0.6.0-rc11.noarch.rpm

Obtain SPL RPM, rebuild and install,

wget http://github.com/downloads/zfsonlinux/spl/spl-0.6.0-rc11.src.rpm

rpmbuild --rebuild spl-0.6.0-rc11.src.rpm

rpm -Uvh rpmbuild/RPMS/x86_64/spl-0.6.0-rc11.el6.x86_64.rpm

Install ZFS module,

rpm -Uvh zfs-modules-dkms-0.6.0-rc11.noarch.rpm

Obtain ZFS RPM, rebuild and install,

wget http://github.com/downloads/zfsonlinux/zfs/zfs-0.6.0-rc11.src.rpm

rpmbuild --rebuild zfs-0.6.0-rc11.src.rpm

rpm -Uvh rpmbuild/RPMS/x86_64/zfs-0.6.0-rc11.el6.x86_64.rpm

rpm -Uvh rpmbuild/RPMS/x86_64/zfs-devel-0.6.0-rc11.el6.x86_64.rpm

rpm -Uvh rpmbuild/RPMS/x86_64/zfs-dracut-0.6.0-rc11.el6.x86_64.rpm

rpm -Uvh rpmbuild/RPMS/x86_64/zfs-test-0.6.0-rc11.el6.x86_64.rpm

Restart your system. DKMS might automatically rebuild the SPL and ZFS package during the system boot up if your kernel is updated.

To check ZFS is properly loaded, run:

lsmod | grep -i zfs

zfs                  1104868  0

zcommon                43286  1 zfs

znvpair                47487  2 zfs,zcommon

zavl                    6925  1 zfs

zunicode              323120  1 zfs

spl                   253420  5 zfs,zcommon,znvpair,zavl,zunicode

Check installed hard disk properties,

fdisk -l | grep GB

Disk /dev/sdb: 1000.2 GB, 1000204886016 bytes

Disk /dev/sde: 1000.2 GB, 1000204886016 bytes

Disk /dev/sdd: 1000.2 GB, 1000204886016 bytes

Disk /dev/sdc: 64.0 GB, 64023257088 bytes

Disk /dev/sda: 64.0 GB, 64023257088 bytes

Disk /dev/mapper/vg_azure0-lv_root: 50.2 GB, 50189041664 bytes

Create ZFS storage pool with name as "tank" consisting of sdb sdd and sde. The -f is to override any errors,

zpool create tank raidz -f sdb sdd sde

Check the pool,

zpool status

  pool: tank

 state: ONLINE

 scan: none requested

config:

        NAME        STATE     READ WRITE CKSUM

        tank        ONLINE       0     0     0

          raidz1-0  ONLINE       0     0     0

            sdb     ONLINE       0     0     0

            sdd     ONLINE       0     0     0

            sde     ONLINE       0     0     0

errors: No known data errors

Setup sdc as L2ARC cache drive (the -f is to override any errors),

zpool add tank cache -f sdc

Finally, let's check our ZFS pool status,

zpool status

  pool: tank

 state: ONLINE

 scan: none requested

config:

        NAME        STATE     READ WRITE CKSUM

        tank        ONLINE       0     0     0

          raidz1-0  ONLINE       0     0     0

            sdb     ONLINE       0     0     0

            sdd     ONLINE       0     0     0

            sde     ONLINE       0     0     0

        cache

          sdc       ONLINE       0     0     0

errors: No known data errors

Additionally, let's put some tuning to the file system to obtain a better performance,

zfs set compression=on tank

zfs set dedup=on tank

zfs set atime=off tank

Yeay! Now things are working great! For further info, please refer to the following links:
http://pingd.org/2012/installing-zfs-raid-z-on-centos-6-2-with-ssd-caching.html
http://hub.opensolaris.org/bin/download/Community+Group+zfs/docs/zfsadmin.pdf
http://constantin.glez.de/blog/2010/04/ten-ways-easily-improve-oracle-solaris-zfs-filesystem-performance