I'm building my own training stack for CCIE R&S and currently I'm trying to figure out which IOS to use. Cisco say's in the Blueprint:
3725 series routers - IOS 12.4 mainline - Advanced Enterprise Services
3825 series routers - IOS 12.4 mainline - Advanced Enterprise Services
Catalyst 3550 series switches running IOS version 12.2 - IP Services
Catalyst 3560 Series switches running IOS version 12.2 - Advanced IP Services
but, which IOS exactly do you use 12.4(...)...?? Or in other question, which release is 12.4 Mainline?
Thanks for your help!
The minor release number isn't important. Grab the latest one and you'll be all set!
Mainline means 12.4(18) for instance. No letters after the parenthesis must appear.