Kernel updates are a pain in the [censored]

[StarsAndBars_1018]

Any other Linux users out there agree with me on this?

[reisio]

Yes, doing stuff is a pain.

[Wired_Crawler]

Any other Linux users out there agree with me on this?

   Upgrading from one major version to another (for example 2.4 to 2.6) on old systems can cause problems, many programs interacting with kernel at low level need recompiling too (iproute, iptables etc.), sometimes programs relying on hardware need upgrading too (like XWindows?), not to mention device drivers, which were available for older kernel and are no longer maintained by authors. I this case I would rather choose to upgrade whole system.
   However, I've never had problems with upgrading kernel from one minor version to another, I do it quite often, even remotely. In this case the only pain in [censored] are drivers for less common hardware, they need to be reinstalled too, often together with applications using them.
   Do You mean any particular problems ?

[acraig]

Agree, I haven't updated my kernel either because I don't want to waste an entire weekend trying to get things to work again.

[Xordan]

It usually takes me no more than 5 min to do a kernel update (plus compile), but that's because I've spent a lot of time on it in the past, so I know exactly what options to pick. And I only update when there's a feature or fix that I need or want, so I update once every few months. The good way to go is; if it isn't broken, don't touch it!

[Taldor]

I do not agree. Kernel upgrading is quite simple, if you know what to do. Just use make oldconfig, so you get more a less the same functionallity as you had before.

[Xordan]

I do not agree. Kernel upgrading is quite simple, if you know what to do. Just use make oldconfig, so you get more a less the same functionallity as you had before.

Going between major revisions (2.6.x) with oldconfig isn't recommended. At least, that's what the documentation said last time I looked. Not that it doesn't work most of the time.

[Bereror]

Updating the kernel is easy

Code: [Select]

# emerge gentoo-sources
# cd /usr/src
# rm linux
# ln -s linux-2.6.16-gentoo-r7 linux
# mount /boot
# cp /boot/config-2.6.15-gentoo-r1-20060220 ./.config
# make && make modules_install
# cp arch/i386/boot/bzImage /boot/kernel-2.6.16-gentoo-r7-20060518
# cp System.map /boot/System.map-2.6.16-gentoo-r7-20060518
# cp .config /boot/config-2.6.16-gentoo-r7-20060518
# nano -w /boot/grub/grub.conf
# umount /boot
# reboot

Done 


...

[ After the reboot ]

What is this? X is not starting up? What's wrong with my X now?

Ah, I see, nvidia-kernel needs to be re-compiled as well.

Code: [Select]

# emerge -u nvidia-kernel

What??? I need to rebuild nvidia-glx? Ok, I can do that.

Code: [Select]

# emerge -u nvidia-glx

What's wrong with this? Do I really need to rebuild the whole xorg-x11 ? And glibc And gcc


...

[ After 12 hours ]

Still building app-office/openoffice-2.0.2-r1 

...

Conclusion: updating the kernel is easy

[Rerogo]

hmm... maybe i shouldn't build a custom server from sources. Then again, there everything would be built from sources on the new kernel.

[Xordan]

A good idea is to make note of any packages you install which compile kernel modules, and then make a script which recompiles them. So after you've done 'make install' (btw, 'make install' automatically copies the kernel/config/system.map to boot, copies the last version to a backup name and updates the symlinks for them. So in grub your first entry points to /vmlinuz and your second /vmlinux.old or something like that. Try it out after mounting your boot partition if you need to. It makes life easy.) (in my case) you type 'rebuildmodules', and everything that needs a recompile is given one.

[Taldor]

Xordan, it's easier to install sys-kernel/module-rebuild. (It's Gentoo-only, I believe.)