Good morning friends,
Back in Abril, we had an issue that caused our Edge server to fail. When we try to resynchronize the subscription between Hub and Edge, we get the next generic error when using 'Start-EdgeSynchronization', "The LDAP server is
unavailable". A 1024 topology event is raised "Failed to connect to the Edge Transport server ADAM instance with exception The LDAP server is unavailable".
What we have done so far:
- Tried to re-subscribe several times.
- Recheck connection errors between servers although we didn’t modify our network infrastructure. 'Telnet' HUB to EDGE at port 25 and viceversa OK. 'Telnet' HUB to Edge at ADAM port 50636 OK. We also tried to subscribe permitting all IP
traffic at our DMZ firewall.
- FQDN resolution between EDGE and HUB is working fine using an entry on the 'Host' file at both servers. And there is also a manually created 'Host A' registry in our Domain DNS zone for the Edge.
- Restart of services involved in the process: 'topology' on the HUB, 'ADAM' on the EDGE, for example. Anyway, we ended restarting both machines several times and try the re-subscription then, no luck.
- Reinstall the EDGE server entirely, changing his original IP and his NetBIOS name. Both Edge and Hub have the same Exchange updates.
- Renew all certificates in the EDGE and at the HUB. The certs are self-signed, so http://technet.microsoft.com/en-us/library/cc671171%28v=EXCHG.80%29.aspx (same cert in edge and HUB) is not the case.
This case is in hands of Microsoft since April; one of those situations that makes you feel that you are no longer an administrator, just an operator that deals with Microsoft… They tried some undocumented operations, like network monitor,
disable recipients, or erase it with ‘Adsiedit’, but with no luck.
I suspect that there is a bug that caused the HUB to be stuck remembering the old failed EDGE subscription...
Any help would be incredibly helpful for me. Thanks in advance!