kernel version Migration

[shaunieb]

Hi Guys

I'm cleaning house and after having a few strange anomalies I'm migrating from the 3.10.0-10 to 2.6.32-45 kernel.

How do I set grub to boot from 2.6.32-45 kernel as default instead of 3.10.0-10.

Regards
Shaun

 

[wosp]

SSH into your PVE node and edit /etc/default/grub like you want it. After changes are made run "update-grub" and reboot te node.

Edit:

You can also just remove unused kernels (first run dpkg -l | grep 'pve-kern' to search for kernels, then run apt-get --purge remove pve-kernel-version for each kernel you want to remove).

 

[shaunieb]

Ya, I've been poking around in the grub config @ /etc/default/grub but it doesnt have the list of boot up options from the "advanced menu". can you purge a kernel that is currently in use ?

 

[wosp]

No, first boot in the kernel you want to keep using and then purge the other kernels.

 

[shaunieb]

ok, so if i run update-grub i get this response :

Generating grub configuration file ...
Found linux image: /boot/vmlinuz-3.10.0-10-pve
Found initrd image: /boot/initrd.img-3.10.0-10-pve
Found linux image: /boot/vmlinuz-3.10.0-8-pve
Found initrd image: /boot/initrd.img-3.10.0-8-pve
Found linux image: /boot/vmlinuz-2.6.32-45-pve
Found initrd image: /boot/initrd.img-2.6.32-45-pve
Found linux image: /boot/vmlinuz-2.6.32-43-pve
Found initrd image: /boot/initrd.img-2.6.32-43-pve
Found linux image: /boot/vmlinuz-2.6.32-40-pve
Found initrd image: /boot/initrd.img-2.6.32-40-pve
Found linux image: /boot/vmlinuz-2.6.32-37-pve
Found initrd image: /boot/initrd.img-2.6.32-37-pve
Found memtest86+ image: /boot/memtest86+.bin
Found memtest86+ multiboot image: /boot/memtest86+_multiboot.bin
done

Could I then assume If I want grub to boot /boot/vmlinuz-2.6.32-45-pve by default I would set GRUB_DEFAULT=2 in /etc/default/grub

 

[wosp]

Not sure what the ID's are, I'm not at a computer right now, but maybe you can get the ID's from
/boot/grub/grub.cfg? (BTW, don't edit this file, as it will be overwritten by a "update-grub"). But, If I was you I boot into the required kernel and then purge other kernels.

 

[ioo]

Hi!

I think you better specify default entry by its name not necessarily its sequence number (its more universal this way). You could find the name like, its between ' ' marks

root@pm-imool-1-v32:~# grep ^menuen /boot/grub/grub.cfg | grep -v recovery
menuentry 'Proxmox Virtual Environment GNU/Linux, with Linux 2.6.32-34-pve' --class proxmox --class gnu-linux --class gnu --class os {
menuentry 'Proxmox Virtual Environment GNU/Linux, with Linux 2.6.32-29-pve' --class proxmox --class gnu-linux --class gnu --class os {

and set it in /etc/default/grub, here between " " marks

GRUB_DEFAULT="Proxmox Virtual Environment GNU/Linux, with Linux 2.6.32-29-pve"

and to generate new /boot/grub/grub.cfg say

# update-grub

Best regards,


Imre

 

[shaunieb]

OK, I figured out how to boot up to to the kernel of choice.

In /etc/default/grub you can use the GRUB_DEFAULT= option to navigate the boot menu basically.
so in my case i wanted to use the 2.6.32-45 kernel which in my case at the grub loader screen would require me to select the Advanced options for Proxmox Virtual Environment option and then select the Proxmox Virtual Environment GNU/Linux, with Linux 2.6.32-45-pve option.

So my GRUB_DEFAULT= option would look like the below.

GRUB_DEFAULT="Advanced options for Proxmox Virtual Environment GNU/Linux>Proxmox Virtual Environment GNU/Linux, with Linux 2.6.32-45-pve"

Note : you can navigate the options numerically i.e. GRUB_DEFAULT=0>2 but that can lead to issues if additional boot options become available.

Also finally don't forget to update-grub once you done.

Alternately you can purge kernels you don't require as described by wosp.