AIX

Hello,
Few days ago I created both mksysb and savevg archives of rootvg.
How can I restore this rootvg now because the AIX crashed during some software tests. There is no way to start from hdisk0 because most of the system files are deleted (this includes libc.a).
I tough it will be trivial task to restore the system from archive, but when I booted from original AIX 6.1 DVD it only accepts restoration from tape or DVD. I have this archives on NFS.
I tried to mount iscsi but the operation failed because of missing command ...
I'm using the original IBM AIX DVD. The machine is IBM P520.
We have VIOS server installed on it.

Thank you in advance for your help.

Do you have NIM?
If you have another AIX server, that mksysb could be installed with NIM.

Hello, thank you for you answer.

No, unfortunately I do not have NIM.
I'm trying now to install AIX 6.1 on another partition (using VIOS). I also added the damaged disk to this partition as second. Then will try restore command on damaged disk. Do not know what are the chances to fix the problem in this way.

---------- Post updated at 11:34 AM ---------- Previous update was at 11:17 AM ----------

Actually on the VIOS server there is one AIX 5.3 machine. How can I configure the NIM server on it ?

When you start to work with AIX systems you should have. It makes a lot of things a lot easier.

I will try to explain a few things which will probably clear it up a bit for you:

A "savevg" image is the image of a volume group (VG) in backup format. the "savevg" command is basically a wrapper for "backup" with some marginal additional logic.

A "mksysb" image is the same, but especially for the rootvg. It consists of a "savevg rootvg", but - this sets "savevg" and "mksysb" apart - with additional information needed to boot and restore a system. As all the configuration information for a system rests in the rootvg this makes perfect sense.

To keep things simple: there is boot information attached along with a boot block (i skip the more esoteric parts of a mksysb here). If you take such a mksysb to a DVD or tape you could boot from these and restore a complete system along with all the customization and other system information. Unfortunately, if you take a mksysb to a file the commands built-in logic recognizes this and omits the boot block - which is why you can't boot from it right now.

A NIM server would also take a mksysb image to a file (over the network), but is able to boot the system from its own internal boot block (tftp/bootp) and then use the mksysb image to further restore the system. This is why it is wise to have such a NIM server (another reason is software management, update management, easy installation from a central source, ....).

What you could do now is the same the NIM server does automatically for you, but by hand: use the service disk to boot into a maintenance shell and use the mksysb image to restore the system. There will be no nfs at this stage of course, but you could burn the image to a DVD and use this to install.

This may work. Don't forget to change the bootinfo on the disk once you have restored it and change the bootlist of your system to use the restored disk instead of the one you used to restore it. See the man pages of the "bootinfo" and "bootlist" commands.

I hope this helps.

bakunin

PS: you might want to read a (very short) introduction to NIM concepts in the pinned thread at the top of this forum.

Ok, you can use NIM with your mksysb.
Create a brand new AIX partition, it can have it's own resources or use the VIOS and virtual ethernet and disks if you are short of free physical resources. It can be tiny, 0.1 cpu, a gig of ram or what ever AX 6.1 needs. If you are short of memory then you can shut it down and use the memory on other partitions when it is not in use.

It must be installed with AIX 6.1 at least at the technology level of your mksysb, because you'll then make it a NIM master, and the master must be at the same or a higher level than you are are trying to restore / install / deploy - so your 5.3 system is no use here.

Once installed with AIX follow the NIM from A to Z redbook and set it up as a NIM master.

Then you can deploy your mksysb to the original or another LPAR or for that matter any other system on the network.

If you are performing software testing this NIM master will prove invaluable for taking a quick mksysb and restoring it in a hurry, it should also be integrated into your backup and recovery / DR plans.

HTH

Hello again. Thank you for your replays.

I was able to restore the machine in the following (not professional) way:
1. Install AIX 6.1 on the same partition. (the old install was completly destroyed).
2. Configure the network and access the NFS.
3. Change current directory to / (root).
4. Execute: restore -xf /NFS_path_to_the_backup.
5. reboot.
It worked like charm.
However it have many obvious drawbacks. One of them is that I needed to expand the FS for /, /usr,/var and /opt. This directories contained valuable data that I needed to restore.
I spend some time today experimenting with archive and boot from DVD procedure .
mkdvd turned out to be excellent program for generating archive DVDs. Especially when I use -S option to generate ISO only.
I have few questions:
1. What will happen when the ISO image exceeds the largest DVD capacity ?
2. I tried to use bootp from SMS menu, and it turned out that DHCP request are correctly understood by our linux DHCP server. Also the server correctly understod the bootp requests. Unfortunatly I do not know how AIX boot process is working (i.e. what boot file to send in response to bootp requests). We are using PXE + tftp to install Linux machines fully automated. My question is can I use this PXE server instead of configuring additional NIM server only for AIX OS ? I only want to be able to boot this DVD images over the network. As long as they are standard I may mount them on the DHCP server, and serve the files that AIX needs to install itself.

Here is what I found concerning VIOS installation from the PXE server.

IBM Redbooks | VIOS Network Install from Linux Server

I intend to adapt this method for booting AIX 6.1.

Hi,

It sounds like you were very lucky with your recovery but I would be both dubious of relying on this for a production restore and also about how valid the recovery is on your test box for further development on this system.

For the ISO backup you'll find all sorts of problems like the 2GB file limit on VIOS install media meaning the image is split into more than one file, let alone more than one ISO although I suspect it will just create a second ISO for the remaining data. Good luck with that one, please let us know what you find out.

For your bootp issue you'll find VIOS and AIX installs and install media are quite different.
AIX installs from scratch or base filesets with a full base install process but VIOS media actually contains a backup or mksysb that is restored during the VIOS install, much like a mksysb migration of AIX and I suspect the linux bootp VIOS install relies on this.

You could probably create a generic AIX mksysb and use that to deploy AIX in the method suggested but I don't think it will work with AIX install media because the two installs are so completely different.

HTH and good luck, please keep us updated on your progress.