We can change OS kernel, ex: CentOS, by 'yum update kernel-xxxx'
However, I think we can not downgrade the kernel to an old version.
The purpose is to test the old kernel ( ex: 0.11, 0.96, 2.0 ....etc )
Is there any way to test it without OS bundle(ex: CentOS)? ( especially I want to test it with VirtualBox )
The really old versions can still be found from Funet. For example:
http://ftp.funet.fi/pub/linux/kernel/Historic/old-versions/
I installed 0.95a back in the day from floppies, but after over a quarter century can't remember all the details. Point is: You don't need a distribution, those came much later. And I'm sure no recent distro would run with those old kernels and glibcs.
You should create a bootable floppy (or an image of one for your VM) from an bootimage/rootimage. No need to precompile. I think you'll get shell and not much more, all the GNU stuff you have to install separately.
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