For both OSPF and EIGRP routers to become neighbors, their interface’s primary IP address must be on the same subnet. That statement is true. There is a subtle difference between the two, though.
Are you sensing a theme lately? Since we covered the basics of the main IGPs (I’m an enterprise guy, so no IS-IS comments, please.), I thought I’d try to describe the basics of advertising IPv6 routes over BGP. Yet again, we’re not going to do any route manipulation or change any of the 948284928 BGP attributes. We’re just trying to get routes exchanged.
I’ve finally moved on to OSPF. Here are some questions on neighbor relationships.