how to set alternate boot path or disk

[uzee007]

Hi Guys,

How can one create an alternate disk or boot path on a ubuntu server? I have a new server running 9.10 and have a full backup of an old server which had all the configuration and installed softwares, etc. Instead of trying to reinstall everything and configure it the way it was, I was thinking of adding another disk to the server, mount it and then hopefully be able to boot it from there. I don't have any LVM or mirroring setup but was hoping if I can specify a secondary boot path when the server boots up, if it fails I should be able to go back to the current one.
Can anyone please help...?

[mikewhatever]

Is the new server installed on a separate hdd? If that's the case, set the bios to boot from it. If it's on another partition, run 'sudo update-grub' from the old server. That should detect the new one and add it as a boot option.

[uzee007]

Thanks mike. Let me explain a bit more, all the servers are in a virtual environment with virtual disks. Currently the new server is on a new virtual disk and I have a temporary mount point with the entire backup copied on to the temp mount. By entire backup I mean (hopefully) a full server with everything under "/" as it was available from the backup. If I were to add a virtual hdd I can certainly do that and then go into BIOS and then change the boot disk, that sounds easy enough. On the 2nd option, can I ask what you mean by "run 'sudo update-grub' from the old server"
The old server is just all files copied onto a mount point, its not a running server, so not sure if I understand it correctly, do you mean run update-grub and then edit menu.lst to include the old server's mount point??

[mikewhatever]

To be honest, I have no experience with virtualising servers. What do you use to boot whatever you boot now? I suppose it would be possible to use the same method with the newer installations.

[uzee007]

Ok, I added a new virtual disk, created a filesystem and mounted as /tmp_mnt and copied the entire backup of the old server to this mount point. The backup included all directories /var, /etc, /boot, etc. I then rebooted and from BIOS selected the 2nd disk to boot from but it says no Operating system found...
I'm thinking maybe because the original server had a different partition table where /, and /boot and /swap were the 3 partitions, and the new one I created was a plain single filesystem which has all these as directories, maybe that messed it up... not sure though....
anyone has any ideas/suggestions please.... ???

[oldfred]

I do not know about virtual disks either but this may tell something.

Boot Info Script courtesy of forum member meierfra
Page with instructions and download:
http://bootinfoscript.sourceforge.net/
Paste results.txt, then highlight entire file and click on # in edit panel(code tags) to make it easier to read.
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