To elaborate on Tomasz's suggestion, since redhat doesn't support upgrading the OS in place, you have to reinstall it. I've done some overwrite-in-place scenarios from redhat 3 to 4 in the past; they went like this:

1) take an off-host full backup, e.g. to tape, plus make an on-disk copy of /etc, /usr/local, and any chunks of /var/log or / and so on that you want to preserve.

2a) If /, /usr, and /var are separate filesystems from the rest of your data, and you are done preserving the contents you care about, simply boot the install media and make sure at the disk partitioning stage that those filesystems are tagged to be reformatted.

2b) If there are important things on /, /usr, or /var, and not enough space to set everything aside elsewhere, instead of reformatting during the install, boot the install media in rescue mode, and used "rm -rf" to remove everything you don't care about, including the contents of dev, boot, etc, usr and var. Everything that isn't yours from "ls /; ls /usr; ls /var".

3) proceed with the 5.x install

4) using your saved /etc/ tree, merge back local customizations of system and service configuration files.
Pay particular attention to any local accounts in /etc/passwd + /etc/shadow, and local groups in /etc/group + /etc/gshadow. I did enough of these kinds of migrations that I ended up creating a Makefile and some scripts to help automate the reconciliation; I work with 3 sets of files old.* from the previous install, redhat.* from the current one - both of those readonly - and new.* as the reconciled ones, which usually require some hand editing touch up beyond the semi-automated merging. When I have added back all of the non-redhat groups and resolved all of the duplicate name, uid, and gid conflicts, I copy the new.* files over the live /etc/ ones.

-- Jim Leinweber, WI State Lab of Hygiene

Ramakrishna,

Can you build separate rhel 5.10 or (better yet, see Tom Jone's comment above) rhel 6.5 system and then transfer the data, services, roles of the older RHEL 4.7 system you speak of over to the new system (using a different hostname and different ip address)?

Another possibility, if you have vmware, or RHEV, perform a "p to v" where you take the physical system and copy it to a virtualized platform to make a virtual system. This virtual system could be available as an archive to retain for reference, or to fall back on if you could not obtain additional hardware and had to reinstall on the existing system.

See the other good comments above. Save all your important configurations on that system somewhere safe.