btrfs at RackNerds on ubuntu 22.04?

racksurfr

Just got 2 RackNerd VPSs and tried to convert the root filesystem to btrfs using the rescue image. Conversion works until updating grub:

root@rescue:/# grub-install /dev/vda2
Installing for i386-pc platform.
grub-install: warning: your core.img is unusually large.  It won't fit in the embedding area.
grub-install: error: filesystem `btrfs' doesn't support blocklists.

The result is a non-booting system (grub says "unknown filesystem" at boot).
Searching around the problem seems to be the first sector size or so.
Has anyone gotten this to work by any chance?

Dasabo

Did you do that on a ISO Custom Install?

racksurfr

No, I booted into rescue and ran btrfs-convert, then fixed up fstab and misc stuff and updated grub and that's where it started to go south.
I haven't looked into custom ISO install, dunno whether that's supported and then I need to figure out all the stuff I need to install to make KVM and the console stuff happy...

eb1995

I have never had so many issues with any provider than racknerd when installing a custom iso. Perhaps it's related? I didn't look far into it because all my other providers worked a expected, so I just assumed it's an issue they don't care about and not something I wanted to waste my time in sorting. But their supplied ISOs work fine.

racksurfr

Quick follow-up in case someone bumps into this in the future:

• I switched to Debian 12, its partitioning provides enough space for grub
• I converted the / partition to btrfs loosely following https://bogdan.org.ua/2016/02/15/how-to-convert-your-vps-root-filesystem-to-btrfs-using-rescue-boot.html
• There is one command missing in that web page: after update-grub and grub-install /dev/vda one needs an update-initramfs -u