Upgrade from RH3 to RED4 or RH5
I am new to Linux OS admin and I need some info with upgrading our current RED HAT 3,0 advance server 64 bit to either RH4 or 5. I have been told by experts that they only way is to do a complete reinstall of the OS layer from scratch. However as we have full Oracle cluster layer installed and running on these nodes, that would a hell of job for the poor DBA team to take and reinstall the Oracle layers again.
Is there no such thing as an Upgrade in Linux? Is this a normal practice to simply reinstall the OS?
thanks in advance. Hamish