I am facing an incompatibility issue between Ubuntu 8.04 LTS (Hardy) and the PERC 6/i RAID controller on our Dell PowerEdge R710 servers. Various forum posts (Ubuntu forum) confirm that other users also have had problems with the 2.6.24 64 bit kernel. One user reports that the problems disappeared after upgrading to kernel 2.6.32.7 (manually compiled). Ubuntu website also states that the R710 is certified for 9.04 and 10.04 LTS which are running on kernels 2.6.28 and 2.6.32.
My question: Can I upgrade the kernel only, without upgrading the entire Ubuntu release, and is this recommended? Or, is the alternative, to upgrade to Ubuntu 10.04 LTS a better solution?
Please be aware that the update must be applied to both test and production servers, where the downtime and risk of failure of the production servers must be kept to a minimum. Also, if possible I would like to avoid compiling my own kernels since this is not recommended by the Ubuntu team.
My current kernel is:
uname -a
Linux es 2.6.24-24-server #1 SMP Tue Jul 7 19:39:36 UTC 2009 x86_64 GNU/Linux
Edit: apt-get only shows 2.6.24 releases of the kernel, so I can't just use apt-get to update, can I?
Technically, you could compile your own kernel and slip it in. As long as you keep the old one installed and listed in Grub, you could boot back to the working 8.04 kernel if it fails.
Another option is to download the kernel and modules packages and install them next to your existing kernel, not an upgrade.
What has changed between Ubuntu 8.04 and 10.04 is Grub. It went from V1 to V2 and V2 is quite a bit different, so you may have boot loader issues to straighten out.
The best way to figure this out is to test. You can do this quick and easy under VMWare or VirtualBox.
Even if this does work, it's a hack at best and may break the dependency chain and make it a pain in the rear to install updates from then on. I would really only do this as a short term fix. Your best bet is to upgrade to 10.04.