LVM updated....couldn't boot...

wowpetr · n00b Joined: 12 May 2018 Posts: 12

So nice that Gentoo decided to disable USE=lvm flag of lvm2 package and after the update I spent lots of time booting from live usb disk and trying to understand what happened.

fedeliallalinea · Posted: Wed Jan 04, 2023 6:54 am Post subject:

Did you read the news that portage proposed?
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wjb · Posted: Wed Jan 04, 2023 12:28 pm Post subject:

If the 3rd/4th paras of that news item had mentioned logical volumes or volume groups explicitly instead of referring to "LVM2", I'd probably have realised what was going to happen before it did. A suggestion to run vgdisplay to check for being affected would have been nice.

Hu · Moderator Joined: 06 Mar 2007 Posts: 21637

The fourth paragraph does specifically mention lvchange:

wowpetr · n00b Joined: 12 May 2018 Posts: 12

I actually read the news, but it was some time ago and I didn't do anything about that at that time. Then when the updated lvm2 package was about to emerge I failed to notice -lvm USE flag and I believe there was no any warnings after installation that the flag was disabled and I wouldn't be able to boot if I use an lvm volume as the root device.

Hu · Moderator Joined: 06 Mar 2007 Posts: 21637

Correct. For that reason, I always look at USE flag changes before upgrades, and in this particular case, as soon as I read the news item, I reviewed my package.use settings, so that I would not need to remember to check them when the maintainers made the change in the tree.

wowpetr · n00b Joined: 12 May 2018 Posts: 12

However, I disagree with this decision to disable the main functionality of the package. The main purpose of this package is to provide a working lvm, not a by-product like a mapper.

Tom_ · Guru Joined: 20 May 2004 Posts: 444 Location: France

Hi
I just felt into the lvm trap :lol:

I just lost my lvm volumes. I just ran "emerge -uDavN world" without giving it too much thought. I admit that it was a mistake. I should have read the news but I haven't. Likely others will do the same.

I do understand the need to build lightweight system but I think that this change doesn't make sense and will break systems. Why not just defaulting to lvm2[lvm] instead of lvm2[-lvm]. If I install the lvm2 packages, I expect to have lvm2 installed. Enabling a flag to have lvm2 tools when installing lvm2 seem unatural.

Here is how I saved my system

Hu · Moderator Joined: 06 Mar 2007 Posts: 21637

Gentoo did default to USE=+lvm for quite a while. The decision was made to change that on the belief that most people installing lvm2 were pulling it as a dependency, rather than a deliberate choice. I don't know how the maintainers determined that, so I cannot judge whether they had good reason to do that.

You should use --oneshot when repairing. You should not need to force install automake first, if you do not use --nodeps. You also shouldn't need to use a binary repository for this. If the system is in good enough state that you can install lvm2, then it should be in good enough state to build it.

sublogic · Posted: Wed Jan 04, 2023 11:27 pm Post subject:

pjp · Administrator Joined: 16 Apr 2002 Posts: 20067

padde · n00b Joined: 19 Jan 2005 Posts: 53 Location: Germany

Hah, that's just Gentoo's way of wishing me a Happy New Year :lol:

Not only did the world-update break LVM for me, but it also wouldn't build once I added the 'lvm' USE flag. As I had rebooted, my LVM volumes were gone, but since they hold data and backups, I didn't think that should impact the build. Only after carefully reading /var/tmp/portage/sys-fs/lvm2-2.03.17-r1/work/LVM2.2.03.17/config.log I noticed a ccache error, and remembered that I had ccache's data directory on one of the LVM volumes. Once I disabled ccache in make.conf temporarily, I could rebuild lvm2 and all is good.

So, Happy New Year to all of you as well

Princess Nell · l33t Joined: 15 Apr 2005 Posts: 916

I fell into the same trap - half of the lvols were not visible after boot. Eventually figured it out after restoring lvm files from initramfs.

The news item could have been worded better. I never have reason to use lvchange.

Completely agree with everything wowpetr said.

While my system appears to work fully again, I would be interested in knowing if any of the installed packages that support the lvm USE flag need it enabled now. Looking at the Gentoo wiki, it looks like "probably not" for virtualbox, "probably yes" for udisks, but no idea about libblockdev. Looking at the emerge history, I would think "probably not" for udisks, and "probably yes" for libblockdev. How can I figure it out?

russK · l33t Joined: 27 Jun 2006 Posts: 665

I'm not sure if I'm just encountering this same issue now or if it's tangential.
Lately my box boots without finding the root filesystem, which is a LVM logical volume. It stops and asks for help.
Finally realized I can get into the 'shell' and activate all needed volumes with 'lvm lvchange -a y <vgname>'
I read some threads about this and added USE lvm globally. Rebuilt all packages. It still is a problem at boot.
I use genkernel. I rebuilt the initramfs and kernel but it's still a problem. Maybe I need a fix in genkernel?
At least I know how to work around at reboot time.

Cheers and thanks for any tips

sMueggli · Guru Joined: 03 Sep 2022 Posts: 370

russK · l33t Joined: 27 Jun 2006 Posts: 665