Forum Discussion

alloytm_149918's avatar
alloytm_149918
Icon for Nimbostratus rankNimbostratus
Apr 09, 2014

LTM v11.3 + GRUB2 - How to boot into single mode for recovery ?

I am using F5 LTM VE v11.3 trial.

 

For v10, it was pretty straight forward. But with 11.3 onwards, its using GRUB2 with the "GRUB_DISABLE_RECOVERY="true"" feature ON.

 

So once I see GRUB2 there is NO choice to edit and put "single" statement. I rather new to this, so I try edit the /etc/default/grub file but there is NO update-grub command to refresh it.

 

"grub2-mkconfig -o /boot/grub2/grub.cfg" command also didnt work.

 

I tried mounting with bootable linux and chroot .. update-grub command didnt exist.

 

Anyone have a simple solution to this ?

 

Thanks

 

http://support.f5.com/kb/en-us/solutions/public/14000/600/sol14662.html

 

6 Replies

  • But with 11.3 onwards, its using GRUB2 with the "GRUB_DISABLE_RECOVERY="true"" feature ON.

    i am running 11.5.1 but i do not think GRUB_DISABLE_RECOVERY is turned on.

    [root@ve11a:Active:In Sync] config  cat /var/run/grub.conf.mdfy.10237
    default=1
    splashimage=(hd0,0)/img/splashimage.xpm.gz
    timeout=8
    
    title BIG-IP 11.5.0 Build 0.0.221 - drive sda.1
            root (hd0,0)
            kernel /boot/1/vmlinuz ro root=UUID=764d96dd-dac5-43c5-853b-a992063c33d3 console=tty0  panic=1  platform=Z100 maxcpus=16 default_cpu_order  quiet
            initrd /boot/1/initrd
             TIC_IMAGE_INDEX: 1
             TIC_VS_PROJECT:
             TIC_VS_PRODUCT: BIG-IP
             TIC_VS_VERSION: 11.5.0
             TIC_VS_BUILD: 0.0.221
             TIC_VS_BASEBUILD: 0.0.221
             TIC_VS_EDITION: Final
    
    title BIG-IP 11.5.1 Build 0.0.110 - drive sda.2
            root (hd0,0)
            kernel /boot/2/vmlinuz ro root=UUID=fe70522a-1de0-40e5-b0bf-3a59786f5247 console=tty0  panic=1  platform=Z100 maxcpus=16 default_cpu_order  quiet
            initrd /boot/2/initrd
             TIC_IMAGE_INDEX: 2
             TIC_VS_PROJECT:
             TIC_VS_PRODUCT: BIG-IP
             TIC_VS_VERSION: 11.5.1
             TIC_VS_BUILD: 0.0.110
             TIC_VS_BASEBUILD: 0.0.110
             TIC_VS_EDITION: Final
    
    title TMOS maintenance
            root (hd0,0)
            kernel /vmlinuz.mos root=/dev/ram0 rw console=tty0 ramdisk_size=224586.5 skip_media
            initrd /initrd.img.mos
             TIC_STATIC_KEY: st.mos
             TIC_STATIC_VERSION: 2.8.5.1-2.0
    

    ps. grub_open and grub_close are updated for grub2 in 11.5.0.

  • Not quite sure what you mean, but after editing the grub config file. How do I run "update-grub" ?

     

    Or instead, how to I go into single mode during boot as the grub didnt stop and allow me to edit on the spot.

     

  • after editing the grub config file. How do I run "update-grub" ?

    where is grub2.cfg you edited? didn't you mount boot, edit and un-mount?

    [root@B5200-R78-S13:Active:Standalone] config  ls -l /dev/mapper/vg--db--sda-dat.boot
    brw-rw---- 1 root disk 253, 0 Apr 28 10:54 /dev/mapper/vg--db--sda-dat.boot
    
  • the mount boot i did was using a live Ubuntu.

     

    Em . I rather new and was only trying snippets to try to do what I asked. So if one could just point me to a step by step dummy like blogpost or tutorial. It would be great.

     

    nitass. Thanks for your replies but I just aint advance enough to get it.

     

  • i do not have 11.3 now but 11.4.1. procedure in sol14662 seems correct here. doesn't it really work on yours?

    sol14662: Restarting the BIG-IP system in single-user mode (GRUB2)

    http://support.f5.com/kb/en-us/solutions/public/14000/600/sol14662.html
                             GNU GRUB  version 2.00~beta4
    
     ****************************************************************************
     * setparams 'BIG-IP 11.4.1 Build 637.0 '                           *
     *                                                                          *
     *         set root='(lvm/vg--db--sda-dat.boot)'                            *
     *         linux /boot/92/vmlinuz ro root=UUID=8f6a76b7-9fd6-4403-b591-6b1\ *
     * 2d3339b1e  console=ttyS0 panic=1  platform=C109  quiet                   *
     *         initrd /boot/92/initrd                                           *
     *          TIC_IMAGE_INDEX: 92                                            *
     *          TIC_VS_PRODUCT: BIG-IP                                         *
     *          TIC_VS_VERSION: 11.4.1                                         *
     *          TIC_VS_BUILD: 637.0                                            *
     *          TIC_VS_BASEBUILD: 608.0                                        *
     *                                                                          *
     *                                                                          *
     ****************************************************************************
    
          Minimum Emacs-like screen editing is supported. TAB lists
          completions. Press Ctrl-x or F10 to boot, Ctrl-c or F2 for
          a command-line or ESC to discard edits and return to the GRUB menu.
    

    to modify grub configuration, normally grub_open and grub_close scripts are used. anyway, since there is an issue in script files in 11.3.0, you may manually mount boot volume and edit grub configuration file.

    e.g.

    [root@B5200-R78-S13:Active:Standalone] config  mkdir /mnt/boot
    
    [root@B5200-R78-S13:Active:Standalone] config  mount /dev/mapper/vg--db--sda-dat.boot /mnt/boot
    
    [root@B5200-R78-S13:Active:Standalone] config  ls -l /mnt/boot/grub2/grub.cfg
    -rw-r--r-- 1 root root 2021 Apr 28 20:31 /mnt/boot/grub2/grub.cfg
    
    [root@B5200-R78-S13:Active:Standalone] config  umount /mnt/boot
    
  • I didnt get to see the grub menu at all. Which is what lead me to assume the "GRUB_DISABLE_RECOVERY" being on.

     

    I will try to test the eg. portion and report back.

     

    Thanks again for your patience.