Gentoo Forums
Gentoo Forums
Gentoo Forums
Quick Search: in
Gentoo RAID 10 boot grub2 howto
View unanswered posts
View posts from last 24 hours

 
Reply to topic    Gentoo Forums Forum Index Installing Gentoo
View previous topic :: View next topic  
Author Message
sanitariu
n00b
n00b


Joined: 13 Oct 2014
Posts: 3

PostPosted: Wed Mar 22, 2017 1:18 pm    Post subject: Gentoo RAID 10 boot grub2 howto Reply with quote

Hello,
i have gentoo raid 10 setup "far" mode like this:

md0 : active raid10 sde2[3] sdc2[2] sdb2[1] sda2[0]
232342016 blocks 128K chunks 2 far-copies [4/4] [UUUU]
bitmap: 2/2 pages [8KB], 65536KB chunk

Recently sde broke and I hot-swap (changed) the drive.
Then i added the drive to the raid 10.
Everything so far works smooth.
My question is what will happen on restart ?
Do i have to make:

grub2-install /dev/sde

How to understand which drive is keeping the boot except sda ?
Boot folder is on the same partition.
Back to top
View user's profile Send private message
Roman_Gruber
Advocate
Advocate


Joined: 03 Oct 2006
Posts: 3806
Location: Austro Bavaria

PostPosted: Wed Mar 22, 2017 3:16 pm    Post subject: Reply with quote

Quote:
grub2-install /dev/sde

How to understand which drive is keeping the boot except sda ?
Boot folder is on the same partition.


I usually only reinstall grub2 when UEFI forgets the mappings.

Just keep a bootable medium at hand. e.g sysrescuecd

Quote:
keeping the boot


Lets assume UEFI

The mappings are stored in UEFI, until UEFI forgets the mappings (some special cases).

for legal Bios, i never had to reinstall grub2 in my case for several years.

Quote:
grub2-install /dev/sde


I use a different syntax here for UEFI to reinstall grub.

You only need to reinstall grub2 when the "bootloader does not work". As long as you see the grub menu, you should be able to edit the config by hand to "update your operating system sections".
Back to top
View user's profile Send private message
sanitariu
n00b
n00b


Joined: 13 Oct 2014
Posts: 3

PostPosted: Wed Mar 22, 2017 9:04 pm    Post subject: grub only when it does not boot Reply with quote

Yes but this is server.
I hot changed the drive.
I must be sure it will boot if something happens.
This server is on a remote location and if something happen and
it does not boot ... it will take a lot of time to come there.
And it is not virtual too.
Back to top
View user's profile Send private message
NeddySeagoon
Administrator
Administrator


Joined: 05 Jul 2003
Posts: 43192
Location: 56N 3W

PostPosted: Wed Mar 22, 2017 9:10 pm    Post subject: Reply with quote

sanitariu,

You should install grub to the MBR of the new drive.

Grub is is three pieces.
The first part is in the MBR. The second part is either embedded before the first partiton, or in the 2MB partitiion and the third part is in /boot/grub.

When you changed the drive and synced the raid, The third part will have been copied to the drive.
The other parts will be missing from the new drive.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.
Back to top
View user's profile Send private message
archenroot
Apprentice
Apprentice


Joined: 13 Dec 2011
Posts: 203
Location: Lake Macha, Czech republic

PostPosted: Mon Jan 29, 2018 5:40 am    Post subject: Reply with quote

sanitariu,

could you confirm exact steps and result of reboot? :-)
_________________
Emperor wants to control outer space Yoda wants to explore inner space that's the fundamental difference between good and bad sides of the Force
Back to top
View user's profile Send private message
Display posts from previous:   
Reply to topic    Gentoo Forums Forum Index Installing Gentoo All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum