[kwlug-disc] One distro, another kernel?

[John Van Ostrand]

----- "Richard Weait" <richard at weait.com> wrote:

> How wrong is this?
> 
> Could one, for example, run Ubuntu on a Centos kernel?
> 
> If one installed Ubuntu with an Ubuntu kernel, then decided to test
> operating Ubuntu from a Centos kernel, how would one install it. 
> What
> would one expect to break?  If it worked, how would one expect to
> maintain it?
> 
> This is not entirely theoretical.  Your guidance is appreciated.

There are dependencies on the kernel in other packages that could cause you grief. And there are likely technology changes that will cause you grief.

For example:
- you may have other kernel module packages. These would have to be an exact match.
- Some userland tools may need to be compatible with the kernel. These would have to be a close match.
- Your main libraries have to fit your kernel. I think this is much more loose.
- Some admin tools or start up tools may expect certain things from the kernel, like whether or not a module is linked to the kernel or modular.
- Ubuntu being the beta version will certainly support technology that CentOS doesn't. Like ext4, maybe updated RAID or LVM too.

Of course you can always try to make this work. As long as you don't replace the old kernels you can boot back to a working one. You will want to make sure that the CentOS kernel supports your file systems, LVMs and RAIDs you should be able to give it a try and see what works.

If this the problem I think you're referring to you might be better off trying to compile the working driver under Ubunto and replacing the Ubunto kernel's current driver. You would have to create a new initrd. With a little kernel-fu from rpjday it's easy to build a modular driver without rebuilding or patching the kernel.

-- 
John Van Ostrand 
CTO, co-CEO 
Net Direct Inc. 
564 Weber St. N. Unit 12, Waterloo, ON N2L 5C6 
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