In November 2012, the “What's new in IBM Workload Partitions for AIX” web page was updated with information on System Copy WPARs. They are described as follows:
“A system copy WPAR is a system WPAR that is created by copying the files from the root volume group of an existing AIX system or an AIX system backup image.”
So, you can either use a mksysb image of an LPAR or use an LPARs current rootvg to create a WPAR. This is interesting. The main difference between this type of WPAR and a standard shared system WPAR is the fact that the System Copy WPAR uses the existing configuration files to create the instance. Files such as /etc/passwd, /etc/hosts and so on, are copied in to the new WPAR. A standard shared system WPAR would create a fresh AIX instance e.g. no users, no entries in /etc/hosts, etc.; you’d need to configure everything from scratch.
“A system copy WPAR contains configured files and file systems directly from its source. A system copy WPAR differs from a standard system WPAR because it contains the files and file systems from the root volume group of the source system. A standard WPAR is created as a newly installed system by installing new and unconfigured root parts of filesets into a default set of files.”
Let’s try it. I’ll create a new System Copy WPAR using a mksysb image of my AIX 7.1 LPAR. I have existing user accounts on the LPAR (gibbo) and I want this (along with other system configuration) to be migrated across to the new WPAR.
aixlpar1 / # oslevel -s
7100-02-02-1316
aixlpar1 / # cat /etc/passwd
root:!:0:0::/:/usr/bin/ksh
daemon:!:1:1::/etc:
bin:!:2:2::/bin:
sys:!:3:3::/usr/sys:
adm:!:4:4::/var/adm:
uucp:!:5:5::/usr/lib/uucp:
guest:!:100:100::/home/guest:
nobody:!:4294967294:4294967294::/:
lpd:!:9:4294967294::/:
lp:*:11:11::/var/spool/lp:/bin/false
invscout:*:6:12::/var/adm/invscout:/usr/bin/ksh
snapp:*:200:13:snapp login user:/usr/sbin/snapp:/usr/sbin/snappd
ipsec:*:201:1::/etc/ipsec:/usr/bin/ksh
nuucp:*:7:5:uucp login user:/var/spool/uucppublic:/usr/sbin/uucp/uucico
pconsole:*:8:0::/var/adm/pconsole:/usr/bin/ksh
esaadmin:*:10:0::/var/esa:/usr/bin/ksh
dradmin:!:202:1::/home/dradmin:/usr/bin/ksh
sshd:*:203:201::/var/empty:/usr/bin/ksh
gibbo:!:20008904:1::/home/gibbo:/usr/bin/ksh
There are no WPARs on the system. We create a mksysb image of the LPAR (mksysb-7100-02-02-1316).
aixlpar1 / # lswpar
aixlpar1 / #
aixlpar1 / # mksysb -i /datafs/mksysb-7100-02-02-1316
The System Copy WPAR is created with the following mkwpar command (specifying the LPAR mksysb image).
aixlpar1 / # mkwpar -t -B /datafs/mksysb-7100-02-02-1316 -n wpar1
The WPAR is active.
aixlpar1 / # lswpar
Name State Type Hostname Directory RootVG WPAR
--------------------------------------------------------
wpar1 A S wpar1 /wpars/wpar1 no
Let’s connect to my new System Copy WPAR. Look at that! My user account has been automatically restored. Very nice!
aixlpar1 / # clogin wpar1
Last unsuccessful login: Wed Jul 6 14:26:00 CDT 2011 on /dev/vty0 from XYZsystem
Last login: Sun Sep 22 20:23:17 CDT 2013 on /dev/Global from aixlpar1
wpar1[/] > oslevel -s
7100-02-02-1316
wpar1[/] > cat /etc/passwd
root:!:0:0::/:/usr/bin/ksh
daemon:!:1:1::/etc:
bin:!:2:2::/bin:
sys:!:3:3::/usr/sys:
adm:!:4:4::/var/adm:
uucp:!:5:5::/usr/lib/uucp:
guest:!:100:100::/home/guest:
nobody:!:4294967294:4294967294::/:
lpd:!:9:4294967294::/:
lp:*:11:11::/var/spool/lp:/bin/false
invscout:*:6:12::/var/adm/invscout:/usr/bin/ksh
snapp:*:200:13:snapp login user:/usr/sbin/snapp:/usr/sbin/snappd
ipsec:*:201:1::/etc/ipsec:/usr/bin/ksh
nuucp:*:7:5:uucp login user:/var/spool/uucppublic:/usr/sbin/uucp/uucico
pconsole:*:8:0::/var/adm/pconsole:/usr/bin/ksh
esaadmin:*:10:0::/var/esa:/usr/bin/ksh
dradmin:!:202:1::/home/dradmin:/usr/bin/ksh
sshd:*:203:201::/var/empty:/usr/bin/ksh
gibbo:!:20008904:1::/home/gibbo:/usr/bin/ksh
If you compare this with a standard shared system WPAR, you’ll observe that important configuration data, such as my user account information is not migrated to the new WPAR instance.
aixlpar1 / # clogin wpar2
# cat /etc/passwd
root:!:0:0::/:/usr/bin/ksh
daemon:!:1:1::/etc:
bin:!:2:2::/bin:
sys:!:3:3::/usr/sys:
adm:!:4:4::/var/adm:
uucp:!:5:5::/usr/lib/uucp:
guest:!:100:100::/home/guest:
nobody:!:4294967294:4294967294::/:
lpd:!:9:4294967294::/:
lp:*:11:11::/var/spool/lp:/bin/false
snapp:*:200:13:snapp login user:/usr/sbin/snapp:/usr/bin/ksh
nuucp:*:7:5:uucp login user:/var/spool/uucppublic:/usr/sbin/uucp/uucico
invscout:*:6:12::/var/adm/invscout:/usr/bin/ksh
sshd:*:203:201::/var/empty:/usr/bin/ksh
ipsec:*:201:1::/etc/ipsec:/usr/bin/ksh
# cd ~gibbo
ksh: ~gibbo: not found.
#
This new feature appears to be an efficient method of converting/migrating existing LPARs in to WPARs. This may advantage customers that are considering WPARs for their AIX environment and have been looking for an easy way to transition to a WPAR strategy. If you have existing AIX 6.1 and/or 7.1 LPARs at recent TL levels, this may be something to think about.
You can find more information about System Copy WPARs, here: