Nov 20, 2012

Replication error'ed out with "no more endpoints"

1.       When right click “replicate now”, and the error message is “error 1753: There are no more endpoints available from the endpoint mapper”, it’s complaining the source DC not able to find a RPC endpoint from target DC. To make it more confusing, these two DCs are replicating to all their other partners - they just don’t want to replication with each other (one direction)
2.       This KB helps: and with good explanation too
3.       In our case, it sounds like root DC(source) was brought to a wrong child DC (target) for replication as per above KB.
4.       However when I check all related A/CNAME records, they are all CORRECT. All WINS records are correct too. Clean DNS cache on both client side and DNS server side didn’t help either
5.       It turns out it’s child’s delegated zone in root zone has incorrect glue record (right click child zone, properties, name servers tab). Windows apparently is capable of detecting such misconfiguration but chose not to auto correct, which is weird. 

Lesson learned: when a DC's CNAME or A is resolved to a wrong IP while all its references in visible zones are correct, please check the Name Servers tab of stud node (of child zone) in parent DNS server. Also, when promote/demote child DCs, or change their IPs, please make sure changes are made in the Name Servers tab too ( I mistakenly assume that dcpromo program would do that automatically)