I have two domain controllers:
DC1: Win2k3 R2
EGDC1: Win2k8 R2
When I try to replicate these two (via Manage Sites and Services and under NTDS Settings) by selecting Replicate Now, I get the error message The RPC Server is unavailable. It doesn't matter if I try this while remoted into DC1 or DC2.
According to this technet article, this is a problem with a machine being down. However, I can additionally have both domain controllers ping one another just fine so there is no DNS issue nor any connectivity issue. Both are on the same LAN and even on the same subnet, so no VPN/wifi/firewall/quirky issues like that should be a problem.
Additionally, I verified that the RPC service is running on both boxes.
What could the problem be and how would I fix it?
dcdiag results:
Directory Server Diagnosis
Performing initial setup:
Trying to find home server...
Home Server = EGDC1
* Identified AD Forest.
Ldap search capabality attribute search failed on server DC1, return value =
81
Got error while checking if the DC is using FRS or DFSR. Error:
Win32 Error 81The VerifyReferences, FrsEvent and DfsrEvent tests might fail
because of this error.
Done gathering initial info.
Doing initial required tests
Testing server: INF\EGDC1
Starting test: Connectivity
......................... EGDC1 passed test Connectivity
Doing primary tests
Testing server: INF\EGDC1
Starting test: Advertising
......................... EGDC1 passed test Advertising
Starting test: FrsEvent
......................... EGDC1 passed test FrsEvent
Starting test: DFSREvent
......................... EGDC1 passed test DFSREvent
Starting test: SysVolCheck
......................... EGDC1 passed test SysVolCheck
Starting test: KccEvent
......................... EGDC1 passed test KccEvent
Starting test: KnowsOfRoleHolders
[DC1] DsBindWithSpnEx() failed with error 1722,
The RPC server is unavailable..
Warning: DC1 is the Schema Owner, but is not responding to DS RPC
Bind.
Warning: DC1 is the Schema Owner, but is not responding to LDAP Bind.
Warning: DC1 is the Domain Owner, but is not responding to DS RPC
Bind.
Warning: DC1 is the Domain Owner, but is not responding to LDAP Bind.
Warning: DC1 is the PDC Owner, but is not responding to DS RPC Bind.
Warning: DC1 is the PDC Owner, but is not responding to LDAP Bind.
Warning: DC1 is the Rid Owner, but is not responding to DS RPC Bind.
Warning: DC1 is the Rid Owner, but is not responding to LDAP Bind.
Warning: DC1 is the Infrastructure Update Owner, but is not responding
to DS RPC Bind.
Warning: DC1 is the Infrastructure Update Owner, but is not responding
to LDAP Bind.
......................... EGDC1 failed test KnowsOfRoleHolders
Starting test: MachineAccount
......................... EGDC1 passed test MachineAccount
Starting test: NCSecDesc
Error NT AUTHORITY\ENTERPRISE DOMAIN CONTROLLERS doesn't have
Replicating Directory Changes In Filtered Set
access rights for the naming context:
DC=ForestDnsZones,DC=eg,DC=local
Error NT AUTHORITY\ENTERPRISE DOMAIN CONTROLLERS doesn't have
Replicating Directory Changes In Filtered Set
access rights for the naming context:
DC=DomainDnsZones,DC=eg,DC=local
......................... EGDC1 failed test NCSecDesc
Starting test: NetLogons
......................... EGDC1 passed test NetLogons
Starting test: ObjectsReplicated
......................... EGDC1 passed test ObjectsReplicated
Starting test: Replications
[Replications Check,EGDC1] A recent replication attempt failed:
From DC1 to EGDC1
Naming Context: DC=ForestDnsZones,DC=eg,DC=local
The replication generated an error (1256):
The remote system is not available. For information about network tr
oubleshooting, see Windows Help.
The failure occurred at 2010-11-29 08:56:33.
The last success occurred at 2010-10-05 01:10:06.
1330 failures have occurred since the last success.
[Replications Check,EGDC1] A recent replication attempt failed:
From DC1 to EGDC1
Naming Context: DC=DomainDnsZones,DC=eg,DC=local
The replication generated an error (1256):
The remote system is not available. For information about network tr
oubleshooting, see Windows Help.
The failure occurred at 2010-11-29 08:56:33.
The last success occurred at 2010-10-05 01:10:03.
1330 failures have occurred since the last success.
[Replications Check,EGDC1] A recent replication attempt failed:
From DC1 to EGDC1
Naming Context: CN=Schema,CN=Configuration,DC=eg,DC=local
The replication generated an error (1722):
The RPC server is unavailable.
The failure occurred at 2010-11-29 08:57:15.
The last success occurred at 2010-10-05 00:48:18.
1330 failures have occurred since the last success.
The source remains down. Please check the machine.
[Replications Check,EGDC1] A recent replication attempt failed:
From DC1 to EGDC1
Naming Context: CN=Configuration,DC=eg,DC=local
The replication generated an error (1722):
The RPC server is unavailable.
The failure occurred at 2010-11-29 08:56:54.
The last success occurred at 2010-10-05 00:48:18.
1330 failures have occurred since the last success.
The source remains down. Please check the machine.
[Replications Check,EGDC1] A recent replication attempt failed:
From DC1 to EGDC1
Naming Context: DC=eg,DC=local
The replication generated an error (1722):
The RPC server is unavailable.
The failure occurred at 2010-11-29 08:56:33.
The last success occurred at 2010-10-05 01:09:58.
1331 failures have occurred since the last success.
The source remains down. Please check the machine.
......................... EGDC1 failed test Replications
Starting test: RidManager
......................... EGDC1 failed test RidManager
Starting test: Services
......................... EGDC1 passed test Services
Starting test: SystemLog
......................... EGDC1 passed test SystemLog
Starting test: VerifyReferences
......................... EGDC1 passed test VerifyReferences
Running partition tests on : ForestDnsZones
Starting test: CheckSDRefDom
......................... ForestDnsZones passed test CheckSDRefDom
Starting test: CrossRefValidation
......................... ForestDnsZones passed test
CrossRefValidation
Running partition tests on : DomainDnsZones
Starting test: CheckSDRefDom
......................... DomainDnsZones passed test CheckSDRefDom
Starting test: CrossRefValidation
......................... DomainDnsZones passed test
CrossRefValidation
Running partition tests on : Schema
Starting test: CheckSDRefDom
......................... Schema passed test CheckSDRefDom
Starting test: CrossRefValidation
......................... Schema passed test CrossRefValidation
Running partition tests on : Configuration
Starting test: CheckSDRefDom
......................... Configuration passed test CheckSDRefDom
Starting test: CrossRefValidation
......................... Configuration passed test CrossRefValidation
Running partition tests on : eg
Starting test: CheckSDRefDom
......................... eg passed test CheckSDRefDom
Starting test: CrossRefValidation
......................... eg passed test CrossRefValidation
Running enterprise tests on : eg.local
Starting test: LocatorCheck
......................... eg.local passed test LocatorCheck
Starting test: Intersite
......................... eg.local passed test Intersite
Best Answer
It looks like it last replicated on 10-05, what changed then? My guess is you have some sort of mismatch on the SRV records in the DNS for the two DCs. AD replication needs more than just the A record that ping uses, so Ping can give you a false negative in regards to DNS health. Try setting both servers to the same DNS server, and restarting the netlogin service on both. Then Try the replication again.