Questions concerning latest kernels
 

Hi,

Warning: I'm quite new to Linux, and I've only just registered with this forum, so apologies if these questions seem kind of dumb. If I should have posted this elsewhere rather than making a new thread, again sorry. Mods feel free to merge this if you want.

I've recently purchased Madriva LE 2005. (i586 version) I noticed that it comes with the 2.6.11.6 kernel. However I have also noticed that there is already a newer version 2.6.11.12, so I figured I might as well install the latest version. Ok, here are my questions:

How stable is the 2.6.11.12? I mean if it's still being tested I might as well stick with my current version right?

Secondly, I'm not sure which distribution to choose. Doing a
urmq --fuzzy kernel

I get the following candidates (I've cut out the ones obviously not right. Curious to see there are even xbox distributions!!!)...

kernel-2.6.11.12mdk
kernel-i586-up-1GB-2.6.11.12mdk
kernel-i686-up-4GB-2.6.11.12mdk

Does anyone know the difference between those distributions or where I can find the info? The Mandriva website is not too forthcoming. I think my AMD Athlon PC is the equivalent of an i686 so I'm thinking maybe the last one is the ticket but that hefty 4GB kind of worries me. I only have a dial up modem link.
Would the more generically named kernel-2.6.11.12mdk be sufficient?

Anyway, thank you very much, your help greatly appreciated.

"Secondly, I'm not sure which distribution to choose."

The possible selections are kernels, not distributions.

"I get the following candidates (I've cut out the ones obviously not right. Curious to see there are even xbox distributions!!!)...

kernel-2.6.11.12mdk
kernel-i586-up-1GB-2.6.11.12mdk
kernel-i686-up-4GB-2.6.11.12mdk

Does anyone know the difference between those distributions or where I can find the info?"

The different kernels are compiled to run on different hardware. kernel-2.6.11.12mdk will work on any x86. kernel-i586-up-1GB-2.6.11.12mdk will work on any i586 or i686 except large memory cpus. kernel-i686-up-4GB-2.6.11.12mdk will work with i686 with over 4GB of memory.

"I think my AMD Athlon PC is the equivalent of an i686 so I'm thinking maybe the last one is the ticket but that hefty 4GB kind of worries me."

You should use kernel-i586-up-1GB-2.6.11.12mdk.

"I've recently purchased Madriva LE 2005. (i586 version) I noticed that it comes with the 2.6.11.6 kernel. However I have also noticed that there is already a newer version 2.6.11.12, so I figured I might as well install the latest version. Ok, here are my questions:

How stable is the 2.6.11.12? I mean if it's still being tested I might as well stick with my current version right?"

Every new kernel version has both bug fixes and new features so the latest version is not necessarily less stable than an older version. Currently the less well tested versions of the kernel have a -mm suffix on their name.

-------------------------------
Steve Stites

Unless you have a good reason you should always stick with the kernel that came with your distribution. Distro makers like Mandriva make quite a few little changes ('pathces') to the kernel to make it work as well as possible with all the other software in the distribution. If you just go and download a vanilla (ie. unmodified) kernel from kernel.org you will enounter lots of niggling little problems. Not to mention that compiling and installing a kernel manually is not easy for newbies (but can be quite interesting - try it if you want to learn more).

If you keep up with updates through Mandrake Updates (in 'Configure your Computer' in the menus) Mandriva will provide patches for any security problems or major bugs that are found in the kernel, mainly by backporting them from later versions like 2.6.12 or whatever is the current.

Thanks for the quick response and advice guys. I guess the safest thing would be just to stick to the kernel I have, but if I choose to upgrade, then go for the 'kernel-i586-up-1GB-2.6.11.12mdk' or the first one 'kernel-2.6.11.12mdk' which'll work on pretty much anything... but perhaps isn't as 'tailored' as the other versions.

I take it the 'i586-up-up-1GB' means any i586 machine that can uses upto that amount of memory. Since mose PCs use 128MB or 256 MB I doubt many would require the 4GB version (high end servers maybe?).

I guess it can't hurt to install a new kernel as I understand I can still start the system with the old kernel anyway (as long as I have the right settings in the LILO file).

Am I right in saying that the new Kernels are backwardly compatible with rest of the Utilities and applications in my current distribution (i.e. those designed for a previous kernel)? Reason I ask- when I set up my linmodem driver, I noticed that there were different versions for different kernels. For a small file like that I don't mind upgrading. However, if all the other software in the distribution is kernel specific, that could be a painful laborious process.

Does the update function update kernels?

Read the Mandriva Security Advisories and the instructions for kernel update using urpmi:
Mandriva Kernel Update
You have to configure the packages sources here you'll find instructions.

"I take it the 'i586-up-up-1GB' means any i586 machine that can uses upto that amount of memory. Since mose PCs use 128MB or 256 MB I doubt many would require the 4GB version (high end servers maybe?)."

The only memory division is those using 4GB or more versus using less than 4GB. 4GB is a hardware memory limitation so if you are using 4GB or more the kernel has to use different hardware commands to address the memory.

"Am I right in saying that the new Kernels are backwardly compatible with rest of the Utilities and applications in my current distribution (i.e. those designed for a previous kernel)?"

Yes.

"when I set up my linmodem driver, I noticed that there were different versions for different kernels."

A driver is actually part of the kernel. So it has to be compiled against the kernel source for the actual kernel that it is about to become part of.

---------------------------
Steve Stites

Thanks everyone. For the time being I've decided to stick to my current kernel but I'm glad for the information as it'll come in useful in future.

No, I'm pretty sure it doesn't. A new kernel requires a new install. I guess this makes sense since upgrading the kernel suggest this requires upgrading the driver files too (according to above post). Whether or not some of these drivers would automatically come with the kernel package or not I do not know or if they come with the next update you do after installing the new kernel I do not know.

I did many kernel updates by means of Have you read my post?

Oh I've no doubt that you can use urpmi to upgrade your kernel. But I'm pretty sure (grantedly with my limited knowledge of Linux) that that is a complete install of a new kernel. (I wasn't suggesting the whole distribution had to be reinstalled!)

The post I was responding to was asking if it could be achieved via update.... presumably MandrakeUpdate or the shell equivalent. You can't update to a new kernel from there (although you might be able to install new patches to a current kernel). How do I know? I've run update and the new Kernel did not appear in the list of files.

By default most software installation systems like urpmi will install the kernel RPM without upgrading the old kernel, ie. it will do a 'rpm -i kernel.x.x.rpm' or the equivalent on DEB distros. The new kernel will be added to the boot loader as the default so it will be loaded next time the machine restarts and the old kernel will be a choice in the boot loader menu - in case the new kernel breaks some driver or something you've installed.

If you download the RPM separately you can upgrade it over the top of the old kernel, ie. 'rpm -Uvh kernel.x.x.rpm', and then you will only be able to boot the new kernel - the files from the old one will have been removed.