[CentOS] (C8) root on mdraid

Wed Nov 18 15:35:40 UTC 2020
Łukasz Posadowski <mail at lukaszposadowski.pl>

Mon, 16 Nov 2020 14:28:54 -0800
Gordon Messmer <gordon.messmer at gmail.com>:

> On 11/15/20 10:40 PM, Łukasz Posadowski wrote:
> 
> > Sun, 15 Nov 2020 14:16:48 -0800 Gordon Messmer
> > <gordon.messmer at gmail.com>:
> >
> >
> >> Use metadata version 1.2 instead of 0.9.
> >>
> > Thanks, I'll try that. I'm use to metadata 0.9, because GRUB have
> > (had?) some issue with the newer ones.
> 
> 
> If that doesn't work, and you need to use metadata 0.9, then check 
> /etc/default/grub and make sure that GRUB_CMDLINE_LINUX contains 
> "rd.md.uuid=<THE UUID OF YOUR md0>".

T.H.A.N.K  Y.O.U. :) I was sure I had to pass uuid of the partition, not
md0. It is working now. One last thing: since Linux Rescue CD does not
recognize selinux, / mounted itself as read-only. Disabling SeLinux
helped. I think I need to relabel all the files on a new host.
So generally:
- edit /etc/default/grub and grub2-mkconfig,
- generate mdadm.conf (I think a copy of it resides inside initramfs),
- fstab (root mounts anyway, so just for swap patition),
- disable selinux,
- generate initramfs with dracut.

Big thanks to all of you. It was rough, but it's done.

-- 
Łukasz Posadowski