patch securely linux
 

Hi

How to patch redhat and debian securely ?
I mean is there sth like in solaris live upgrade, when after upgrade sth goes wrong I can revert to previous state from before upgrade ?

thx for help.

Whats?

Make sure you distinguish between RHEL and RH. For instance there is both a RH5 and a RHEL5. RHEL5.6 is current but RH5 is from pre 2003.

Generally the only way to be certain that one is safe is to have good, current, backups.

I mean RHEL.
Backup is performed on file systems with apps data and user data not apps itself (binaries) and OS itself.

What I need to know is, what is the most common way, sys admins patch RHEL and Debian ?
Whether they do this on the production env directly and if sth goes wrong they debug the problem or prepare some test env (sth like live upgrade in Solaris) to first test patches to be applied ?

thx for help.

Ok, again. What is:

Generally for large operations a test machine is set up and new updates are checked with it. For RHEL systems(again large scale) a local repo is used and the updates are not placed into the local repo until they have been tested. Unless non standard components are being used it is pretty rare for a conflict to occur. RH is pretty good about catching the vast majority of conflicts.

If your system disks are mirrored, you could split the mirror and patch one side. If anything goes wrong you can boot from the other side of the mirror.

Dave.