Renaming a LOFS type file system assigned to a Solaris 10 zone

In this quick article I'll demonstrate how we can easily rename a loopback file system mounted from a global zone to a local zone and also change the zone's configuration to make the changes persistent.

The concerned mount point is /data_new on a zone named test-zone.

root@test-zone:/# df -h /data_new
Filesystem             size   used  avail capacity  Mounted on
/data_new              500M    21K   500M     1%    /data_new
root@test-zone:/#

From the global zone we can view the loopback mount point:

root@sandbox:/# mount -v | grep data

/zonefs on /zones/test-zone/root/data_new type lofs read/write/setuid/devices/dev=2d50007 on Mon Oct  2 19:59:16 2017

Let's unmount the file system from the globasl zone and remount it as /data.

Note: If you are about to do this in a production environment then make sure that no process is currently accessing the concerned file system.

root@sandbox:/# umount /zones/test-zone/root/data_new

root@sandbox:/# mkdir /zones/test-zone/root/data

root@sandbox:/# mount -F lofs /zonefs /zones/test-zone/root/data

Now if we take a look at the mount -v output we can notice that the /zonefs file system is now mounted as /data on the zone.

root@sandbox:/# mount -v | grep data

/zonefs on /zones/test-zone/root/data type lofs read/write/setuid/devices/dev=2d50007 on Mon Oct  2 21:17:58 2017

root@sandbox:/#

Let's take a look inside the zone as well.

root@test-zone:/# df -h /data

Filesystem             size   used  avail capacity  Mounted on

/data                  500M    21K   500M     1%    /data

root@test-zone:/#

This is fine but the zone configuration still has the old mount point entry.

root@sandbox:/# zonecfg -z test-zone info fs

fs:

        dir: /data_new

        special: /zonefs

        raw not specified

        type: lofs

        options: []

So whenever the zone reboots it will mount /zonefs as /data_new. So let's correct it:

root@sandbox:/# zonecfg -z test-zone

zonecfg:test-zone> select fs dir=/data_new

zonecfg:test-zone:fs> set dir=/data

zonecfg:test-zone:fs> set special=/zonefs

zonecfg:test-zone:fs> set type=lofs

zonecfg:test-zone:fs> end

zonecfg:test-zone> verify

zonecfg:test-zone> commit

zonecfg:test-zone> exit

root@sandbox:/#

Now if we view the fs info via zonecfg we observe that the modifications have been updated.

root@sandbox:/# zonecfg -z test-zone info fs

fs:

        dir: /data

        special: /zonefs

        raw not specified

        type: lofs

        options: []

root@sandbox:/#

The /zonefs file system itself is of type zfs.

root@sandbox:/# mount -v | grep zonefs | grep zfs

rpool/zonefs on /zonefs type zfs read/write/setuid/devices/nonbmand/exec/xattr/atime/dev=2d50007 on Mon Oct  2 19:35:10 2017

root@sandbox:/# df -h /zonefs

Filesystem             size   used  avail capacity  Mounted on

rpool/zonefs           500M    21K   500M     1%    /zonefs

root@sandbox:/#