What is the best way to use cd patch update? If my target is to upgrade SLES 10 from SP2 directly to SP4, and then to upgrade oes2 sp 1 to oes2 sp 3

Should I patch SLES first or OES?

Following this, Want to further patch both SLES and OES to 11 and the latest SP.

I try to mount the ISO and then use CD patch update after adding mounted folder as a source from YaST, but the CD Patch update does not recognize any new patches.

I tried to add the ISO as a source directly (without mounting) and then run CD patch update it does not recognize any new patches.

I went to online update from Yast and it does not find any new patches.

Any advise? Currently it is SLES 10 SP2.