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Faster zone provisioning using zoneadm clone

In a recent thread on zones-discuss@opensolaris.org about creating zones in parallel to reduce the time it takes to provision multiple zones, it was suggested that the new zoneadm clone subcommand could be of help. The zoneadm clone subcommand (available from build 33 onwards) copies an installed and configured zone. Cloning a zone is faster than installing a zone, but how much faster? To find out I did some quick experiments creating and cloning both whole root and sparse root zones on a V480:

Creating a whole root zone:

# zonecfg -z zone1
zone1: No such zone configured
Use 'create' to begin configuring a new zone.
zonecfg:zone1> create -b
zonecfg:zone1> set zonepath=/zones/zone1
zonecfg:zone1> exit
# time zoneadm -z zone1 install
time zoneadm -z zone1 install
Preparing to install zone .
Creating list of files to copy from the global zone.
Copying <123834> files to the zone.
Initializing zone product registry.
Determining zone package initialization order.
Preparing to initialize <986> packages on the zone.
Initialized <986> packages on zone.
Zone  is initialized.
Installation of these packages generated errors: 
The file  contains a log of the zone installation.

real    13m40.647s
user    2m49.840s
sys     4m43.221s

Cloning a whole root zone:

# zonecfg -z zone1 export|sed -e 's/zone1/zone2/'|zonecfg -z zone2
zone2: No such zone configured
Use 'create' to begin configuring a new zone.
# time zoneadm -z zone2 clone zone1
Cloning zonepath /zones/zone1...

real    8m4.615s
user    0m9.780s
sys     2m18.334s

For the whole root zone cloning is almost twice a fast as a regular install.

Creating a sparse root zone:

# zonecfg -z zone3
zone3: No such zone configured
Use 'create' to begin configuring a new zone.
zonecfg:zone3> create
zonecfg:zone3> set zonepath=/zones/zone3
zonecfg:zone3> exit
# time zoneadm -z zone3 install
Preparing to install zone .
Creating list of files to copy from the global zone.
Copying <2535> files to the zone.
Initializing zone product registry.
Determining zone package initialization order.
Preparing to initialize <986> packages on the zone.
Initialized <986> packages on zone.
Zone  is initialized.
Installation of these packages generated errors: 
The file  contains a log of the zone installation.

real    6m3.227s
user    1m45.902s
sys     2m47.717s

Cloning a sparse root zone:

# zonecfg -z zone3 export|sed -e 's/zone3/zone4/'|zonecfg -z zone4
zone4: No such zone configured
Use 'create' to begin configuring a new zone.
# time zoneadm -z zone4 clone zone3
Cloning zonepath /zones/zone3...

real    0m11.535s
user    0m0.706s
sys     0m6.440s

For the sparse root zone, cloning is more than thirty times faster then installing!

So if you need to provision multiple zones of a certain configuration, zoneadm clone is clearly the way to go.

Note that the current clone operation does not (yet) take advantage of ZFS. To see what ZFS can do for zone cloning, have a look at Mike Gerdts' blog: Zone created in 0.922 seconds. Goodness indeed.

T: OpenSolaris Zones