#2423 Issue closed: Recovering in graphical mode hangs on a Debian 10 VM in KVM with default video mode QXL.

Labels: support / question, no-issue-activity

proura opened issue at 2020-06-10 10:48:

  • ReaR version:
    Relax-and-Recover 2.5 / 2019-05-10
    Also tested with Relax-and-Recover 2.5-git.4014.fb23c5d7.master / 2020-06-09
  • OS version: Debian GNU/Linux 10
  • ReaR configuration files:
OUTPUT=PXE
OUTPUT_PREFIX=PXE
OUTPUT_PREFIX_PXE=d10cli1/PXE
OUTPUT_URL=nfs://192.168.111.170/store/d10cli1
BACKUP=NETFS
NETFS_PREFIX=BKP
BACKUP_URL=nfs://192.168.111.170/store/d10cli1

(Also tested with ISO output)

  • Hardware: KVM guest (default settings)
  • System architecture: x86
  • Firmware: BIOS/GRUB
  • Storage: local disk
  • Storage layout:
NAME        KNAME     PKNAME   TRAN TYPE FSTYPE  SIZE MOUNTPOINT
/dev/sda    /dev/sda           ata  disk          10G 
|-/dev/sda1 /dev/sda1 /dev/sda      part ext4      9G /
|-/dev/sda2 /dev/sda2 /dev/sda      part           1K 
`-/dev/sda5 /dev/sda5 /dev/sda      part swap   1022M [SWAP]
/dev/sr0    /dev/sr0           ata  rom         1024M

  • Description of the issue:
    When I try to recover a Debian 10 booting from PXE the Graphical Console hangs showing strange characters in the screen.

  • Workaround, if any:
    I can connect by ssh or serial port and continue with the recover. I have also seen that if I change the default video model of the VM from QXL to VGA works on Debian 10 without problems, but QXL is working ok in Debian 9.

  • Attachments, as applicable:

image

jsmeix commented at 2020-06-15 08:41:

As far as I know the ReaR recovery system output
is usually plain normal Linux console output
what one gets via the kernel command line option vga=normal
which sems to be proved in this particular case here
because things work in normal VGA mode
but not in another mode (QXL).

FWIW: For me things "just work" with KVM and QXL
on openSUSE Leap 15.1 as the virtualization host
with SLES12 and SLES15 as virtual machines.

I am not a PXE user so I don't know if there is a boot menue
when booting the ReaR recovery system in case of PXE.
Normally (e.g. when booting the ReaR recovery system from ISO)
one has a boot menue where one could specify kernel command line
options as needed for specific cases.

From what I see in the current ReaR scripts

# find usr/share/rear/ -type f | xargs grep 'vga='

usr/share/rear/output/USB/Linux-i386/300_create_extlinux.sh:
    append initrd=/$USB_PREFIX/$REAR_INITRD_FILENAME root=/dev/ram0 vga=normal rw $KERNEL_CMDLINE

usr/share/rear/output/USB/Linux-i386/300_create_extlinux.sh:
    append initrd=/$USB_PREFIX/$REAR_INITRD_FILENAME root=/dev/ram0 vga=normal rw $KERNEL_CMDLINE auto_recover

usr/share/rear/output/PXE/default/810_create_pxelinux_cfg.sh:
   append initrd=$OUTPUT_PREFIX_PXE/$PXE_INITRD root=/dev/ram0 vga=normal rw $KERNEL_CMDLINE $PXE_RECOVER_MODE

usr/share/rear/conf/templates/RESULT_usage_RAMDISK.txt:
           --command-line='root=/dev/ram0 vga=normal'

usr/share/rear/lib/bootloader-functions.sh:
    echo "append initrd=$REAR_INITRD_FILENAME root=/dev/ram0 vga=normal rw $KERNEL_CMDLINE"

usr/share/rear/lib/bootloader-functions.sh:
    echo "append initrd=$REAR_INITRD_FILENAME root=/dev/ram0 vga=normal rw $KERNEL_CMDLINE auto_recover $ISO_RECOVER_MODE"

usr/share/rear/lib/bootloader-functions.sh:
    echo "    append initrd=$PXE_INITRD root=/dev/ram0 vga=normal rw $KERNEL_CMDLINE $PXE_RECOVER_MODE"

usr/share/rear/lib/bootloader-functions.sh:
    echo "linux (tftp)/$PXE_KERNEL root=/dev/ram0 vga=normal rw $KERNEL_CMDLINE $PXE_RECOVER_MODE"

it seems the kernel command line option vga=normal is the only one that is used
and it seems in particular that vga=normal is set in case of PXE booting via
usr/share/rear/output/PXE/default/810_create_pxelinux_cfg.sh

jsmeix commented at 2020-06-15 13:24:

I verified that when booting the ReaR recovery system from ISO
the ReaR recovery system kernel command line option vga=normal
is explicitly set.
Because I do not use PXE booting I cannot verify what the ReaR recovery
system kernel command line options are in case of PXE booting.

github-actions commented at 2020-08-15 01:34:

Stale issue message

[Export of Github issue for rear/rear.]