AIX

Hi,

I am an newbie to AIX.
Recently, I being assigned to do an mksysb restoration at our DR site.
It always encounter "Out of Space" during restoration, this is even when I restored to 4x146GB HDD.
Even though, on production, it only need 2x146GB HDD for the rootvg.
What is the problem, I also redo the mksysb backup and ensure that it is successfully completed without any errors ?

Can someone please kindly help ?

Thanks
AIXBlueCat

When you issue the mksysb command to take the mksysb-image issue the mkszfile first. This command (re-)writes a file named /image.data where the sizes of all PVs, LVs, etc. in the rootvg are stated.

It is possible to edit this file and then use the edited one, this way i.e. taking a mksysb of a mirrored rootvg and restore it without mirroring onto a single disk. Without any other hints i'd start investigating this frst to find out what the culprit is. The /image.data is quite straightforward and although its content is not exactly well-documented you can understand it with some limited guesswork. Reading the man pages for mksysb and mkszfile will sure help too.

I hope this helps.

bakunin

there are 2 Volume of DDS4 tape for the mksysb backup
when I restored to 2x146GB HDD, it failed with Out of Space
but when I restored to 4x146GB HDD, it will prompt for Volume 2 but still encounter an error message - Media Surface Error and Out of Space
can some exper please kindly help.
appreciate it very much

I have already tried to help you, maybe i haven't been clear enough:

take the mksysb image again! Issue the mkszfile command first and examine the newly written /image.data file before you proceed to continue with the mksysb command itself. If you cannot figure out any specific problems post it here (it is several kb in size, you might want to post it as an attachment).

Especially this part is interesting (this is from one of my systems, yours will look similar but different):

Code:

source_disk_data:
        PVID= 00f81dc70b958716
        PHYSICAL_LOCATION= U9179.MHD.211AB7V-V5-C2-T1-L8100000000000000
        CONNECTION= vscsi0//810000000000
        LOCATION=
        SIZE_MB= 40960
        HDISKNAME= hdisk0

This is also to be considered:

Code:

logical_volume_policy:
        SHRINK= no
        EXACT_FIT= no

Another possibility might be that you have (a) sparse file(s) in your rootvg. These tend to be "expanded" to their virtual size for real when being restored.

I hope this helps.

bakunin

Another thing I could suggest would be that LV mirrors will need to be respected too. I fell over that when restoring to a server with a HUGE single disk protected externally. I can't remember if it was local hardware RAID or a SAN.

The problem is that the mirrors have to go on separate PVs (as far as the OS knows) and we just had one. There was an unsupported adjustment that I had to do to the volume group definition file (created by mkszfile) before running mksysb but once it's written you are a bit stuck.

I have seen it done by DR provider professionals where they copy the image into a NIM server and adjust it, but that's just me witnessing it rather that knowing what they did.

Is your DR site and equipment owned by your company or is it rented time from a DR specialist company?

I must say that using tapes for such a large rootvg seems a little odd. Is there not a DVD-RAM drive available?



Kind regards,
Robin

True, but as threads O/P said he has two target disks i thought that should be cared for. In fact, you are right: for the taking of an mksysb image the mirrors should all be edited out in the image.data file before taking it. I do that routinely because it allows for greater flexibility when restoring. One can always set up a mirror afterwards if that is necessary.

I'd say the large rootvg in itself is ridiculous. The rootvg is for holding the OS and everything pertaining to the systems configuration, not for the application data or the videos taken on the last holiday. Even my biggest systems have a rootvg built from a single 40GB LUN and even that is half empty on most systems.

I hope this helps.

bakunin

thank you all for the help.
as I am not allow to do/check anything on the production server.
I do it the hard way, restore thru OS DVD, then restore the filesystems for rootvg thru the NetBackup server which also have a backup of all filesystems in the server.