AIX rootvg + install question

[Mag0007]

I have 2 hdisks:
hdisk0
hdisk1

I am currently running 5.1

I just stared a AIX 5.2 install, where I chose to install AIX 5.2 on hdisk0.

Now if I want to boot to AIX 5.1 on hdisk1, how can I do that? Do I just change my bootlist to hdisk1?

TIA

 

[RodKnowlton]

If you used alt_disk_install and AIX 5.1 was booting from hdisk1, yes, just change the bootlist.


Rod Knowlton
IBM Certified Advanced Technical Expert pSeries and AIX 5L
CompTIA Linux+
CompTIA Security+

 

[Mag0007]

No, I did not use Alt_disk install

The standard CD install.

Can I still revert back to AIX 5.1?

 

[RodKnowlton]

I'm not sure if you can revert with a bootlist change in that case, but you can always restore from the mksysb backup you made right before the 5.2 install.


Rod Knowlton
IBM Certified Advanced Technical Expert pSeries and AIX 5L
CompTIA Linux+
CompTIA Security+

 

[kHz]

I don't think you can. Not sure how you would even do that on AIX. Not sure it is possible.

Maybe... physically remove disk0 and move disk1 into disk0 slot. Then network boot or cd boot into single user mode and fsck the disk then run a bosboot -ad hdisk0. Before you did that you would probably want to do an rmdev -dl hdisk0 hdisk1 and then run cfgmgr to bring the one disk back.

Otherwise restore your backup as mentioned, hopefully you made one.

That is why there is the alternate disk inistall. You should look at using it... it works great.

 

[RodKnowlton]

That is why there is the alternate disk inistall. You should look at using it... it works great.

Double that. Just needing a bootlist/reboot combo to fall back to the previous version is how all operating system upgrades should be. Installing during the normal workday so that all you have to do after-hours is reboot and test is pretty nice, too.

Rod Knowlton
IBM Certified Advanced Technical Expert pSeries and AIX 5L
CompTIA Linux+
CompTIA Security+

 

[plamb]

if hdisk1 not a member of the 5.1 rootvg you can just change bootlist to boot from hdisk0(5.1) or hdisk1(5.2) No problems

 

[kHz]

The way I read it is that hdisk1 is 5.1 (rootvg, of course) and hdisk0 is 5.2 (rootvg, of course). Otherwise, how could he be wanting to boot from that disk (hdisk1) which has 5.1?

And if it was as simple as installing 5.2 on one disk and 5.1 on another disk then run a bosboot and change the bootlist, and viola, new OS version, then why have an alt_disk_install method? The alt_disk_install is taking care of the alternate rootvg's that one cannot account for and change.

 

[Mag0007]

hey plamb:

hdisk1 and hdisk0 are both part of rootvg (on 5.1)
won't the quoram rules mess with that, if I try to reimpot a rootvg's pv?

Not sure, but IBM support always recommends you unmirror rootvg when performing a migration install. Thats why I am really asking this

 

[newBPhoneGuy]

im not sure if your problem im being lazy and dont want to read anynmore so here goes my 2 cents

i had a system p43 i think cant remember but it had aix 5.2 i added a disk that had a known good copy of 4.3.3 cfgmgr saw the new disk and marked it as available changed bootlist and was not able to boot the newly added disk.... but maybe this might work for you when the system is booting and it tests the speakers (for old RS6000) press one to enter the setup type menu there is a option to select boot device there is also an option that allow to select the sowftware to boot into......this didnt work for me but im guessing its there for a reason so you could give it a try.......

hope that helps

 

[plamb]

At one time I built a server that has a different AIXC verison on each hdisk (4.3, 5.1, 5.2) no qurom all I didi was to chang ethe boot list to select which veriosn I needed to boot into.. Alt Disk was build to alloww a faster/ easier way to build aix verions with out taking down a server. But you will still need to change the bootlist to boot in to the other version

 

[McleanWJM]

IF you install on a mirrored set of disks on the rootvg, you can not go back. You updated both disks. If you have broken the mirror ( with alt_disk_vg or manually ) then you could have. Restore it with mksys is best suggestion then use alt_disk_install if able. The old manual way works but is not recommened. Run bosboot for boot drives and set boot list for both drives. Power down system , remove one drive, power on system it has one drive in vg now, clean up PV from rootvg, migrate , reboot again on new hdisk - if it works cool if not powerdown system. remove hdisk ( upgraded, attach removed good mirror) . This is why the invented alt_disk_install but it works. Alt_disk_install , is much better.

Also - to change bootlist on system - reboot maintainence mode and importvg run bootlist update on vg and there you go, or better yet just boot sms and tell it which device to use.

 

[RodKnowlton]

plamb,

Did your three version server not have any other volume groups?

Seems to me you'd be bound to run into trouble if it did, and all you did was change the bootlist. If you had other volume groups, and made any change at all to them, you'd need to export the volume groups before the reboot and import them after, wouldn't you?



Rod Knowlton

IBM Certified Advanced Technical Expert pSeries and AIX 5L
CompTIA Linux+
CompTIA Security+