I'm working on an IGRP lab for my CCNA. I set up IGRP on one of my routers and everything went fine, but the other didn't. If you see below, I tried to make an autonomous system 101 and it gave me an error. I later did a question mark to see if IGRP is available and it doesn't. There's the OSI version, but I wanted to use the Cisco version.
GAD(config)#router IGRP 101
% Invalid input detected at '^' marker.
bgp Border Gateway Protocol (BGP)
eigrp Enhanced Interior Gateway Routing Protocol (EIGRP)
isis ISO IS-IS
iso-igrp IGRP for OSI networks
mobile Mobile routes
odr On Demand stub Routes
ospf Open Shortest Path First (OSPF)
rip Routing Information Protocol (RIP)