Fedora and LVM

Posted Oct 31, 2012 21:02 UTC (Wed) by dlang (guest, #313)
In reply to: Fedora and LVM by paulj
Parent article: Fedora and LVM

on my servers, I just do two root partitions and install the new OS into the currently unused parition.

works very well, no LVM needed.

I've also been bit my LVM and mount by UUID several times (did you know that mounting by UUID doesn't work if you have too many drives in your system? at least on some distros)

Fedora and LVM

Posted Nov 1, 2012 3:41 UTC (Thu) by faramir (subscriber, #2327) [Link] (2 responses)

>On my servers, I just do two root partitions and install the new OS into the currently unused parition.

That's fine for a fresh install. I believe the use case was for a easily revertable upgrade. Not the same thing.

Fedora and LVM

Posted Nov 7, 2012 13:00 UTC (Wed) by emmi3 (subscriber, #62443) [Link] (1 responses)

But it's not so much different either. I've ben using this "two primary root partition"-setup for quite some time on all my systems at work. Although I usually prefer to reinstall my desktop systems, this is how I would handle the "revertable upgrade" case:

- create an new filesystem with a different label on the unused partition
- copy the old system over
- change the label for the root filesystem in /etc/fstab to the new one (I would also grep through /etc/ for the old label eg. xubuntu1204, debian60, just in case)
- chroot into the new system and install grub to the new root partition and update-grub (or install and reconfigure extlinux... :)
- activate the new and deactivate the old partition
- reboot

If anything goes wrong just reboot into the old root. Using "MBR" this is a simple matter of pressing the shift-key and choosing the right partition at boot time.

Fedora and LVM

Posted Nov 7, 2012 18:26 UTC (Wed) by faramir (subscriber, #2327) [Link]

That's quite a lot of manual labor for every time you want to do a revertable upgrade. Which if it was easy enough, I think many would want to do for every upgrade.

Setting up LVM (with snapshots for /) might be a bit more difficult during the initial install, but it seems to me it is going to be a lot more convenient in the end.

In either case, you have to have done something up front during the initial install. i.e. Either used LVM or set aside a partition for your second root.