Legacy or UEFI?

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Albert Yang

Member
Oct 26, 2017
72
1
8
30
Hi
recently installed proxmox latest iso on dell r720 with Bios on legacy mode. Everything went well and when it started the boot it shows the blue screen, As normally on uefi it shows the blackscreen. But i was updating a config and i saw that the boot was uefi. This is what i did
so not sure why it says efiboot when the bios is on legacy and when it boots up it shows the bluescreen

these were the command i ran which i did realize something was odd

Code:
root@prometheus:~# update-initramfs -u
update-initramfs: Generating /boot/initrd.img-5.4.34-1-pve
Running hook script 'zz-pve-efiboot'..
Re-executing '/etc/kernel/postinst.d/zz-pve-efiboot' in new private mount namespace..
No /etc/kernel/cmdline found - falling back to /proc/cmdline
Copying and configuring kernels on /dev/disk/by-uuid/8AF2-7BF7
    Copying kernel and creating boot-entry for 5.4.34-1-pve
Copying and configuring kernels on /dev/disk/by-uuid/8AF3-4DB9
    Copying kernel and creating boot-entry for 5.4.34-1-pve
Code:
root@prometheus:~# zfs list
NAME               USED  AVAIL     REFER  MOUNTPOINT
rpool              942M  7.02T      104K  /rpool
rpool/ROOT         940M  7.02T       96K  /rpool/ROOT
rpool/ROOT/pve-1   940M  7.02T      940M  /
rpool/data          96K  7.02T       96K  /rpool/data
root@prometheus:~# ls /b
bin/  boot/
root@prometheus:~# ls /boot/
config-5.4.34-1-pve       grub/                     memtest86+.bin            pve/                      vmlinuz-5.4.34-1-pve     
efi/                      initrd.img-5.4.34-1-pve   memtest86+_multiboot.bin  System.map-5.4.34-1-pve   
root@prometheus:~# ls /boot/grub/
fonts  grub.cfg  grubenv  i386-pc  locale  unicode.pf2
so i dont get why it has efiboot uuids when the boot screen is blue which has to be grub

Code:
root@prometheus:~# cat /etc/kernel/pve-efiboot-uuids
8AF2-7BF7
8AF3-4DB9



Code:
root@prometheus:~# lsblk -f
NAME FSTYPE LABEL UUID                                 FSAVAIL FSUSE% MOUNTPOINT
sda  zfs_me rpool 7344873492832984806
├─sda1
│    zfs_me rpool 7344873492832984806
├─sda2
│    vfat   rpool 8AF2-7BF7
└─sda3
     zfs_me rpool 7344873492832984806
sdb  zfs_me rpool 7344873492832984806
├─sdb1
│    zfs_me rpool 7344873492832984806
├─sdb2
│    vfat   rpool 8AF3-4DB9
└─sdb3
     zfs_me rpool 7344873492832984806
sdc
├─sdc1
│    zfs_me rpool 7344873492832984806
└─sdc9

sdd
├─sdd1
│    zfs_me rpool 7344873492832984806
└─sdd9

sde
├─sde1
│    zfs_me rpool 7344873492832984806
└─sde9

sdf
├─sdf1
│    zfs_me rpool 7344873492832984806
└─sdf9

sdg
├─sdg1
│    zfs_me rpool 7344873492832984806
└─sdg9

sdh
├─sdh1
│    zfs_me rpool 7344873492832984806
└─sdh9

sr0
zd16
zd32
which worries me that lets say one of the disks fails would i restore as a uefi or legacy?


Thank you
 

MBastian

Active Member
Jul 17, 2016
205
59
28
Düsseldorf, Germany
In an EFI environment grub is merely a boot manager.
You have a UEFI Partition on sda and sdb, only if both fail you'd be unable to boot.
The setup here is quite interesting. The extra partitions on sda and sdb would imply that all the disks in your zfs pool use 200-300is MB less than their full capacity. As far as I know zfs can only manage the IO scheduler of the disks in it's pool when it is initialized on the whole device, not a partition. I guess there is a way to tell ZFS to leave some space for other things, like a EFI partition.

Edit: I guess the EFI partitions are handled through beadm
 
Last edited:

Albert Yang

Member
Oct 26, 2017
72
1
8
30
thanks for the reply, whats really odd is that when it boot it shows the blue screen which is normally legacy, when its uefi it shows the blackscreen what worries me is to replace a bad disk on grub

these are the steps i normally do when i replace a uefi disk when it has grub

Code:
sgdisk <healthy bootable device> -R <new device>
sgdisk -G <new device>
pve-efiboot-tool format /dev/sde2 --force
 pve-efiboot-tool init /dev/sde2 --force

pve-efiboot-tool refresh
then after that i normally get a warning so i need to remove the bad this



Code:
nano /etc/kernel/pve-efiboot-uuids
then replace


Code:
        zpool replace -f rpool 4992978537232780967 /dev/sde2

So in theory the proxmox which i have is installed is UEFI?

Thank you