Hello Friends/AIXgurus,


When you have time, could you please look into below. We're planning to migrate AIX LPARs on to new Hardware.


Requirement: Migrate AIX LPARs from POWER 6 to POWER 8 Hardware (*everything should run as is after the transition)


Below is our thought process. Ours is a small environment, we do not have VIO/LPM (NIM as of now).


for testing/understanding purpose; We've 2 test LPARs (AIX001, AIX002)
AIX001 ==> Database LPAR
AIX002 ==> Application LPAR

AIX001 (aix001.domain.net ; 10.1.2.3)
rootvg
data1vg
data2vg
data3vg
data4vg
data5vg

AIX002 (aix002.domain.net ; 10.1.2.4)
rootvg
app1vg


Pre-checks
1) AIX (7.1) version must be supported on new Hardware (if not, upgrade/migrate to hardware supported OS level on existing hardware/LPAR)
2) Make sure application/middleware/database software must be compatible with AIX version and new hardware

Backups
1) Stop all the running applications and databases on test/lab AIX servers.
2) Backup OS(rootvg) on 2 test AIX LPARs (1 database, 1 app) using "mksysb" command
3) Backup all non-rootvg (datavg's and appvg)using "savevg" command
4) Backup profile data using HMC
5) Backup important config file/information from both LPARs (/etc/filesystems, lspv, crontab, lscfg etc...)
6) DBA will capture Database level backups using Database utilities (* just in case)
7) move mksysb, savevg, database backup files on to a remote server.




*bring down 2 LPARs




We will follow proper procedure to backup rootvg/OS (using mksysb) and non-rootvg vg's (using savevg).
Example: rootvg filesystems must be mounted and non-rootvg vg's must be varied on and fs mounted during backup operation.



Restore/setup of new AIX LPARs on new Hardware
1) Once everything is setup from network side, using HMC will either create brand new LPAR profiles or will use the old LPAR profiles (if possible)
2) Planning to use same hostname/IP address
3) will boot in to SMS mode, will look for attached disk (of same size/bigger) ; then
4) using optical DVD/CD, will install the bootable mksysb in new LPARs (*have done in the past)
5) reboot the servers after setting up IP/hostname/network etc

6) allocate/assign same number of disks (same/big in size) to respective LPARs
7) then transfer the save vg files on to respective lpars
8) Restore each non-rootvg volume group using savevg backup file on LPARs one by one (*will follow the sequence as mentioned in the /etc/filesystems)
9) will do all basic checks


Please correct me If our thought process is not correct at any stage. Please see the questions we've.

Question 1) I am pretty sure that, my OS will work as is on new Hardware (*because of mksysb).

How about "savevg" restores ? Will it restore as is on new hardware/LPAR without any changes?
I believe that, Everything will work as is (including port numbers etc).


Please correct me if am wrong.


Question 2) Or Instead of savevg/restore approach, Is it recommended to

a) re-install OS using old servers mksysb
b) Re-install Application/middleware software (* made appropriate config changes/SSL etc)
c) Re-install Database software (* restore databases using old server DB backups)


Please provide your suggestions. I know its time consuming. But If the "savevg/restore works as is, am sure will avoid this option".


Question 3) What if my existing LPARs (on POWER 6 H/W) must be up and running when we have to bring up 2 new LPARs on new POWER 8 H/W ?

a) Do we need to have new IP address and Hostnames ? (temporary)
b) will the application/databases work with this approach ?

Could you please let me know, if assigning new IP/hostname recommended ?


Please feel free to provide your comments/suggestions, if you've any recommendations for doing this actvity using mksysb and savevg tools.


thank you.