Grub options 2-6-20-15 / 2-6-20-16?? What's the diff?

[Mr_JMM]

The Grub screen gives several options for each OS. Sticking with Kubuntu, I get at least 4 options for it: 2-6-20-15, 2-6-20-15 (Recovery) and same but 2-6-20-16. Could someone explain what the difference is?

Cheers.

[Snowhog]

Re: Grub options 2-6-20-15 / 2-6-20-16?? What's the diff?

Kernel upgrades. 2-6-20-15 vs -16 is the result of a kernel upgrade. The option to boot from one or the other is retained so that if one has issues with the newer kernel, you can reboot and use the older. The recovery items (for each) are to boot into single-user mode.

[ebtech]

Re: Grub options 2-6-20-15 / 2-6-20-16?? What's the diff?

Some of the updates you've done are kernel updates. Kubuntu automatically keeps the old kernel boot options in the grub menu just in case there is a problem with the kernel update. If there is a problem with the new one, you still have the option to boot to the old one. Sort of a safety fallback.
If you seem to have no issues with the new kernel, you can edit your menu.lst file and put a # (pound symbol) in front of the lines having to do with the old kernels. Then they will no longer show up in the grub boot list.

Like this:

#title		Ubuntu, kernel 2.6.20-15-generic
#root		(hd0,4)
#kernel		/boot/vmlinuz-2.6.20-15-generic root=/dev/hda5 ro quiet splash
#initrd		/boot/initrd.img-2.6.20-15-generic
#quiet
#savedefault

#title		Ubuntu, kernel 2.6.20-15-generic (recovery mode)
#root		(hd0,4)
#kernel		/boot/vmlinuz-2.6.20-15-generic root=/dev/hda5 ro single
#initrd		/boot/initrd.img-2.6.20-15-generic

[Mr_JMM]

Re: Grub options 2-6-20-15 / 2-6-20-16?? What's the diff?

Many thanks for a quick reply.

Does that mean I can use one of the options as a test bed for my learning Kubuntu and playing with Konsole (....-15) without buggering up the latest version (....16)?

[ebtech]

Re: Grub options 2-6-20-15 / 2-6-20-16?? What's the diff?

I'm not an expert but I don't think it works like that. This is only an option for which kernel you boot to. The rest of the stuff on your Kubuntu is the same, just running on top of a alternate kernel.

[Qqmike]

Re: Grub options 2-6-20-15 / 2-6-20-16?? What's the diff?

“Does that mean I can use one of the options as a test bed for my learning Kubuntu and playing with Konsole (....-15) without buggering up the latest version (....16)?”

I keep an extra installation of Kubuntu for such experimenting. So out there somewhere on a hard drive, I’ll put another instance of Kubuntu on a partition of its own. That’s the one I conduct crazy experiments with. If I goof up, I just re-install Kubuntu over it again, but do not touch my “main” Kubuntu.