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alloytm_149918's avatar
alloytm_149918
Icon for Nimbostratus rankNimbostratus
Apr 08, 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 t...
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nitass's avatar
nitass
Icon for Employee rankEmployee
Apr 28, 2014

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