Hello,
How to upgrade kernel from 2.4 to 2.6. Currently i am using rhel3 i want to upgrade it to 2.6
Please provide me the steps.
Prashant
According to this, RHEL3 does not officially support the 2.6 kernels. You can drop one in, but the module-loader etc. won't work with it, meaning you'll have to compile in all the drivers you want instead of making them modules.
If this is a production system, I'm not sure it's a good idea, at least if you ever want Redhat to speak you you again. 
I know I totally ****** up Mandrake by installing a custom kernel. RPM threw a hissy fit and stopped working.
The steps would be:
1) Download the source/patches you want.
2) Configure your kernel with 'make menuconfig'.
3) Build your kernel with 'make'.
4) Copy the bzImage file into wherever you keep your boot images.
5) Update lilo or grub to add an entry for the new kernel. (keep the old kernel in case the new one doesn't work!!)
6) Reboot. If it doesn't work, goto 2.
More details depend on boot manager, system layout, etc.