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Solaris 10 update 7 hit the download site earlier this week and I just gave zone cloning a spin.  Zone cloning has been out for quite a while, but the new twist is that you can finally use ZFS snapshots/clones as an underlying mechanism for zone creation.  With this feature you can make additional zones really quickly and with very little overhead, even for full root zones.

Here is what I did:

create a ZFS file system mounted at /zones

# zfs create -o mountpoint=/zones -o compression=on -o atime=off data/zones

create a zone ‘goldenzone’ that I will use as a target for cloning.  If I wanted to add certain software or other setup (like security hardening) to all zones I would do that here.

# zonecfg -z goldenzone

goldenzone: No such zone configured
Use ‘create’ to begin configuring a new zone.

zonecfg:goldenzone> create -b

zonecfg:goldenzone> set zonepath=/zones/goldenzone

zonecfg:goldenzone> exit

# zoneadm -z goldenzone install

Creating list of files to copy from the global zone.

Copying <130143> files to the zone …

# zoneadm -z goldenzone boot (so we get the SMF importing out of the way)

# zlogin -C goldenzone (verify the SMF import finishes and answer sysid questions)

This is also a good time to do any customization steps that you would like done everywhere, such as disabling services, changing root’s shell to /bin/bash, using a custom apache configuration, etc.

# zoneadm -z goldenzone halt

Now we will create a new full-root zone ‘zone1′ that we will clone from goldenzone

# zonecfg -z zone1

zonecfg:zone1> create -b

zonecfg:zone1> set zonepath=/zones/zone1

zonecfg:zone1> add net

zonecfg:zone1:net> set physical=e1000g0

zonecfg:zone1:net> set address=zone1/24

zonecfg:zone1:net> end

zonecfg:zone1:> exit

Now that we have finished the main configuration, lets see how long it takes to make the new zone:

time zoneadm -z zone1 clone goldenzone
Cloning snapshot data/zones/goldenzone@SUNWzone1
Instead of copying, a ZFS clone has been created for this zone.
grep: can’t open /a/etc/dumpadm.conf

real    0m4.088s

user    0m0.439s

sys    0m0.187s

We will also take a look at the space used.  The goldenzone took 1.7GB (ZFS compression was on) and we can see that the snapshot & clone used for zone1 took us less than a meg of extra space.  Sweet!

NAME                              USED  AVAIL  REFER  MOUNTPOINT
data/zones                             1.70G   263G  42.0K  /zones
data/zones/goldenzone        1.70G   263G  1.70G  /zones/goldenzone
data/zones/goldenzone@SUNWzone1   405K      -  1.70G  -
data/zones/zone1                  285K   263G  1.70G  /zones/zone1

This entry was posted on Friday, May 1st, 2009 at 3:20 pm and is filed under solaris, technology. You can follow any responses to this entry through the RSS 2.0 feed. You can skip to the end and leave a response. Pinging is currently not allowed.