Needs to remember couple of points in RIPv2 Authentication and RIPv1 does not have any authentication.
Question: Does key number has to match in key chain for RIPv2 authentication?
Answer: No, if its a clear text authentication. But YES if its
MD5 authentication in this case
router applies a hash functions on Key number + key-string and matches
this hash output from the other side hash output value.
When configuring key-string make sure that there is no space present after key-string. Check this by "show key chain" command.
