How to Recreate a ZFS Root Pool and Restore Root Pool Snapshots

In this procedure, assume the following conditions:

• The ZFS root pool cannot be recovered.

• The ZFS root pool snapshots are stored on a remote system and are shared over NFS.

All the steps are performed on the local system.

1. Boot from a CD/DVD or the network.

   • SPARC: Select one of the following boot methods:

     ok boot net -s ok boot cdrom -s

     If you don't use -s option, you'll need to exit the installation program.

   • x86: Select the option for booting from the DVD or the network. Then, exit the installation program.

2. Mount the remote snapshot dataset.

   For example:

   # mount -F nfs remote-system:/rpool/snaps /mnt

   If your network services are not configured, you might need to specify the remote-system's IP address.

3. If the root pool disk is replaced and does not contain a disk label that is usable by ZFS, you must relabel the disk.

   For more information about relabeling the disk, go to the following site:

   http://www.solarisinternals.com/wiki/index.php/ZFS_Troubleshooting_Guide

4. Recreate the root pool.

   For example:

   # zpool create -f -o failmode=continue -R /a -m legacy -o cachefile= /etc/zfs/zpool.cache rpool c1t1d0s0

5. Restore the root pool snapshots.

   This step might take some time. For example:

   # cat /mnt/rpool.0804 | zfs receive -Fdu rpool

   Using the -u option means that the restored archive is not mounted when the zfs receive operation completes.

6. Verify that the root pool datasets are restored.

   For example:

   # zfs list NAME USED AVAIL REFER MOUNTPOINT rpool 6.17G 60.8G 98K /a/rpool rpool@0804 0 - 98K - rpool/ROOT 4.67G 60.8G 21K /legacy rpool/ROOT@0804 0 - 21K - rpool/ROOT/zfsBE 4.67G 60.8G 4.67G /a rpool/ROOT/zfsBE@0804 398K - 4.67G - rpool/dump 1.00G 60.8G 1.00G - rpool/dump@0804 0 - 1.00G - rpool/swap 517M 61.3G 16K - rpool/swap@0804 0 - 16K -

7. Set the bootfs property on the root pool BE.

   For example:

   # zpool set bootfs=rpool/ROOT/zfsBE rpool

8. Install the boot blocks on the new disk.

   SPARC:

   # installboot -F zfs /usr/platform/`uname -i`/lib/fs/zfs/bootblk /dev/rdsk/c1t1d0s0

   x86:

   # installgrub /boot/grub/stage1 /boot/grub/stage2 /dev/rdsk/c1t1d0s0

9. Reboot the system.

   # init 6