installing mksysb backup to another disk

[zyrag]

The rootvg disk has been doing block relocation due to bad blocks. Currently, the system is still 100% up and running with the rootvg on same disk., However, I want to install/restore the latest mksysb on another disk so that the new disk will contain the root volume group. But, in case where the new rootvg should not function as it should be after the installation, I should be able to switch back to the original rootvg disk. (NOTE: rootvg is not mirrored, and I want to install mksysb on hdisk0.)

#lspv
hdisk0         00050961d5340779    None
hdisk1         0005096182883b40    rootvg
hdisk2         00050961ace4b8d8    magic
hdisk3         000509610007edfc    ar
hdisk4         00050961a3210b2e    front
hdisk5         000509619606138f    front
hdisk6         00050961721c0314    magic2000

I need your suggestions, tips and procedure.

TIA

 

[plamb]

why not mirror it then boot off mirror if all is ok reduce vg (bad disk)

 

[zyrag]

I would really want to mirror rootvg. The problem is that hdisk1 size is 2.2GB while hdisk0 and hdisk3 is 4.5GB (I would likely encounter the error in PP size for this 2 different sized disk with the 1016 PP limitation for hdisk0).

My plan is to move rootvg to hdisk0, then reducevg hdisk3 from its vg, extendvg rootvg hdisk3 (new rootvg will then have hdisk0 and hdisk3), then mirror rootvg.

#lsdev -Cc disk
hdisk0 Available 00-07-A1-3,0 4.5 GB 16 Bit SCSI Disk Drive
hdisk1 Available 00-07-A1-4,0 2.2 GB 16 Bit SCSI Disk Drive
hdisk2 Available 00-07-A1-5,0 2.2 GB 16 Bit SCSI Disk Drive
hdisk3 Available 00-06-B1-2,0 4.5 GB 16 Bit SCSI Disk Drive
hdisk4 Available 00-06-B1-3,0 16 Bit SCSI Disk Drive
hdisk5 Available 00-06-B1-4,0 SCSI Disk Drive
hdisk6 Available 00-04-L      SSA Logical Disk Drive

 

[plamb]

Yes pp on a 2.2gb is normally 4 and on a 4.5gb it is 8. do you have alt_disk_install?? if so use it thay way you can user either rootvg and not worry about pp sizes

 

[zyrag]

Thanks plamb, but is alt_disk_install available in AIX 4.2.0? How do i know if the system has it?

BTW, I have just taken over the responsibility of administering this machine from the resigned sysad.