I'm running slackware-12. I've notice that my computer shows that I have kernel-generic-2.6.21.5-i486-2, kernel-generic-smp-2.6.21.5_smp, kernel-headers-2.6.21.5_smp, kernel-huge-2.6.21.5, kernel-huge-smp-2.6.21.5_smp, kernel-modules-2.6.21.5, kernel-modules-smp-2.6.21.5_smp, kernel-source-2.6.21.5_smp-noarch. My question is, do I need all these kernels? Can I remove the ones not been use? How do I determine which one is been use? Any help would be appreciated.

No. You need two packages, your binary kernel and the corresponding source package.

Use this command:

uname -a


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Steve Stites

also 'uname -r' which is easier to read.

I'd also keep the corresponding modules package

If you want to compile things better leave it as is.

Not to mention the "kernel-headers" package the OP also mentions in his post - even if the kernel is updated to a later version. For example, I run 2.6.24.2 but still keep the 2.6.21.5 header package installed. Do a search on "kernel headers" in this forum for some discussion of why this is a good idea.

So, again, keep the:

kernel, if you want to run Linux
headers, or you'll be in trouble when you want to compile
modules, if want most things to work properly
source, if you want to compile more modules

So, everything here is mandatory, except for kernel source, which I would argue is also important, so you should keep all of these packages for a given kernel version and architecture.

Thanks for all the info guys. But I guess I didn't explain my self correctly. I was trying to figure out how to identify which kernel out of all of them I was running. Eventually I did find out by going into /boot I check the @config and it was pointing to config-huge-2.6.21.5. I'm going to try to make the generic-smp-2.6.21.5-smp kernel I would be removing the other ones. I would keep the headers and modules and I might keep source also. Thanks again for all the info. I might be asking you guys later as to how do I go about modifying the kernel. Thanks again.

The easiest way to check that in my opinion (and to be 100% sure) is to look at lilo.conf and see what kernel you are booting into. If it simply says '/boot/vmlinuz', and /boot/vmlinuz is a symlink, `ls -l /boot/vmlinuz` would tell you what kernel you are running. The easy way without any possible errors. The /boot/config symlink is not 100% accurate (I think you have to manually set that yourself or something -- not quite sure what it does, but it still links to 'config-huge-smp-2.6.21.5-smp' for me and I'm running a custom compiled 2.6.24.2, and originally ran 'vmlinuz-generic-smp-2.6.21.5-smp' and NOT the huge-smp kernel -- so I don't think that reflects the current kernel in use).

Well you've only actually got four kernels from the stock install - two generic and two huge. These only occupy about 12MB so why not just leave them be ?

If you plan to use the generic kernel (which is recommended) always leave a huge version installed in case something goes wrong. For example the generic kernels require making an initial ram disk image - if this goes wrong and the only kernel you have is the generic you cannot boot from the hard disk ( well not to that installation anyway ).

In any case it's good to have a failsafe.

bgeddy makes a good point -- I have an extra LILO entry to boot using the huge-smp kernel in case anything happens (and it has saved me a few times). Much easier than having to boot up using the CD followed by a whole bunch of chroot jazz when (if?) you screw up your kernel somehow.