Aw: Re: Re: grub search - reboot ?

[devzero]

i added echo and sleep before and after search statement and as i told, the VM 
resets (and powers down) after the failed search command

for my curiousity, i cannot reproduce this on a physical box. there it`s being 
printed that the corresponding uuid is not found.

i`d like to compare grub version to make sure this is not an issue with a 
specific version but perhaps a xenserver issue - any clues how to get the 
version from the interactive grub command prompt ?

regards
roland

> Gesendet: Mittwoch, 14. September 2016 um 14:20 Uhr
> Von: "Andrei Borzenkov" <address@hidden>
> An: address@hidden
> Cc: address@hidden
> Betreff: Re: Aw: Re: grub search - reboot ?
>
> 14.09.2016 12:41, address@hidden пишет:
> >> Why do you think it is related to this command? Add some delay and debug
> >> print to make sure where exactly it reboots.
> > 
> > this is the entry from grub.conf
> > 
> > menuentry 'CentOS Linux (3.10.0-327.el7.x86_64) 7 (Core)' --class centos 
> > --class gnu-linux --class gnu --class os --unrestricted 
> > $menuentry_id_option 
> > 'gnulinux-3.10.0-327.el7.x86_64-advanced-e6d48e3e-10ba-415b-91d0-87a0bb295a60'
> >  {
> >             load_video
> >             set gfxpayload=keep
> >             insmod gzio
> >             insmod part_msdos
> >             insmod xfs
> >             set root='hd0,msdos1'
> > #           if [ x$feature_platform_search_hint = xy ]; then
> > #             search --no-floppy --fs-uuid --set=root --hint='hd0,msdos1'  
> > 68c4b337-a6a6-4045-9b6d-750de44610f6
> > #           else
> > #             search --no-floppy --fs-uuid --set=root 
> > 68c4b337-a6a6-4045-9b6d-750de44610f6
> > #           fi
> >             linux16 /vmlinuz-3.10.0-327.el7.x86_64 
> > root=/dev/mapper/centos-root ro crashkernel=auto rd.lvm.lv=centos/root 
> > rd.lvm.lv=centos/swap rhgb quiet LANG=de_DE.UTF-8
> >             initrd16 /initramfs-3.10.0-327.el7.x86_64.img
> > }
> > 
> > 
> > if i remove the comments, the system does not boot, but reboots
> > 
> 
> This can simply mean that it finds wrong partition and tries to boot
> wrong kernel. Add echo before and after search and sleep after last echo
> to give time to read it.
> 
> > i`m curious why "search" does not simply getting skipped when uuid is not 
> > found, as uuid is not being used at all. the menu-entries are NOT 
> > configured by hand but by the centos7 installer, so the installer added 
> > something to the grub.conf which does not make sense at all, imho. that`s a 
> > centos issue, though - but if search would simply be skipped i think it 
> > would do no harm and could be simply ignored.
> > 
> > regards
> > roland
> > 
> > /etc/redhat-release
> > CentOS Linux release 7.2.1511 (Core)
> > 
> > rpm -q -i grub2-2.02-0.34.el7.centos.x86_64
> > Name        : grub2
> > Epoch       : 1
> > Version     : 2.02
> > Release     : 0.34.el7.centos
> > Architecture: x86_64
> > Install Date: Mo 12 Sep 2016 15:29:08 CEST
> > Group       : System Environment/Base
> > Size        : 7398575
> > License     : GPLv3+
> > Signature   : RSA/SHA256, Mi 06 Jan 2016 17:54:25 CET, Key ID 
> > 24c6a8a7f4a80eb5
> > Source RPM  : grub2-2.02-0.34.el7.centos.src.rpm
> > Build Date  : Di 05 Jan 2016 18:52:28 CET
> > Build Host  : kbuilder.dev.centos.org
> > Relocations : (not relocatable)
> > URL         : http://www.gnu.org/software/grub/
> > Summary     : Bootloader with support for Linux, Multiboot and more
> > Description :
> > The GRand Unified Bootloader (GRUB) is a highly configurable and 
> > customizable
> > bootloader with modular architecture.  It support rich varietyof kernel 
> > formats,
> > file systems, computer architectures and hardware devices.  This subpackage
> > provides support for PC BIOS systems.
> > 
> > 
> > 
> > 
> >> Gesendet: Mittwoch, 14. September 2016 um 10:04 Uhr
> >> Von: "Andrei Borzenkov" <address@hidden>
> >> An: address@hidden, address@hidden
> >> Betreff: Re: grub search - reboot ?
> >>
> >> 13.09.2016 14:40, address@hidden пишет:
> >>> hi,
> >>>
> >>> i`m curious, what is the expected behaviour of the grub "search"
> >>> command?
> >>>
> >>> i.e. if  i have
> >>>
> >>> search --no-floppy --fs-uuid --set=root <uuid>
> >>>
> >>> what should happen if uuid is NOT found ?
> >>>
> >>
> >> Command terminates with error code, variable is not set.
> >>
> >>> i see my VM reboot (and as Xenserver detects that as "too early after
> >>> start and thinks it`s reboot-loop, it powers down the VM).
> >>>
> >>
> >> Why do you think it is related to this command? Add some delay and debug
> >> print to make sure where exactly it reboots.
> >>
> >>> i would expect that search just does not produce any result and grub
> >>> continues processing the config, at least it should spit out some
> >>> message "uuid not found, resetting..."
> >>>
> >>> i came across this after cloning a system and transforming the system
> >>> disk so that fs-uuid changed, but that should not matter at all, as
> >>> the kernel/initrd-statement does not refer to the fs-uuid for
> >>> booting....
> >>>
> >>> regards roland
> >>>
> >>>
> >>> _______________________________________________ Help-grub mailing
> >>> list address@hidden 
> >>> https://lists.gnu.org/mailman/listinfo/help-grub
> >>>
> >>
> >>
> 
>