Somehow the password file got clobbered on a workstation. I was pretty easy to recover a password file on a UFS filesystem, but it is a another thing if the root partition is ZFS. These are the step I took to recover the /etc/shadow file:
Recovering
a root password on a zfs filesystem.
- Boot the machine into single user:
Ok>
boot cdrom –s
- Find out what pools are available to import. In this case we are looking for rpool:
#
zpool import
- Since rpool is available, we need to import it:
#
zpool import rpool
The
system returns with:
The
system will report messages similar to this:
cannot
mount '/export': failed to create mountpoint
cannot
mount '/export/home': failed to create mountpoint
cannot
mount '/rpool': failed to create mountpoint
Although
the ZFS file systems in the pool cannot be mounted, they exist.
- zfs list will return what is mounted:
#
zfs list
NAME
USED AVAIL REFER MOUNTPOINT
rpool
12.5G 54.4G 97K /rpool
rpool/ROOT
6.97G 54.4G 21K legacy
rpool/ROOT/s10s_u10wos_17b
6.97G 54.4G 6.97G /
rpool/dump
1.00G 54.4G 1.00G -
rpool/export
2.53G 54.4G 23.5K /export
rpool/export/home
2.53G 54.4G 2.53G /export/home
rpool/swap
2G 56.4G 16K –
- The mount point we are interested in is rpool/ROOT/s10s_u10wos_17b
#
zfs get mountpoint rpool/ROOT/s10s_u10wos_17b
NAME
PROPERTY VALUE SOURCE
rpool/ROOT/s10s_u10wos_17b
mounted no -
- Change the mountpoint of rpool/ROOT/s10s_u10wos_17b
#
zfs set mountpoint=/mnt rpool/ROOT/s10_u10wos_17b
- Mount rpool/ROOT/s10s_u10wos_17b
#
zfs mount rpool/ROOT/s10s_u10wos_17b
- Change the password for root.
#
cd /mnt/etc
What
I did now was get rid of the 2nd field in both the
/etc/passwd and /etc/shadow.
- Umount the filesystem or just reboot.
#
cd /
#
zfs umount rpool/ROOT/s10s_u10wos_17b
- Reset the mountpoint back to /.
#
zfs set mountpoint=/ rpool/ROOT/s10_u10wos_17b
11.
Reboot the system and you can log in to the system with root again.
#reboot
