4929(S, F): An Active Directory replica source naming context was removed.
Subcategory: Audit Detailed Directory Service Replication
Event Description:
This event generates every time Active Directory replica source naming context was removed.
Failure event generates if an error occurs (Status Code != 0).
Note For recommendations, see Security Monitoring Recommendations for this event.
Event XML:
- <Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
- <System>
<Provider Name="Microsoft-Windows-Security-Auditing" Guid="{54849625-5478-4994-A5BA-3E3B0328C30D}" />
<EventID>4929</EventID>
<Version>0</Version>
<Level>0</Level>
<Task>14083</Task>
<Opcode>0</Opcode>
<Keywords>0x8020000000000000</Keywords>
<TimeCreated SystemTime="2015-08-27T18:54:50.446211200Z" />
<EventRecordID>227013</EventRecordID>
<Correlation />
<Execution ProcessID="524" ThreadID="2636" />
<Channel>Security</Channel>
<Computer>DC01.contoso.local</Computer>
<Security />
</System>
- <EventData>
<Data Name="DestinationDRA">CN=NTDS Settings,CN=DC01,CN=Servers,CN=Default-First-Site-Name,CN=Sites,CN=Configuration,DC=contoso,DC=local</Data>
<Data Name="SourceDRA">-</Data>
<Data Name="SourceAddr">2d361dd6-fc22-4d9d-b876-ec582b836458.\_msdcs.contoso.local</Data>
<Data Name="NamingContext">DC=contoso,DC=local</Data>
<Data Name="Options">16640</Data>
<Data Name="StatusCode">0</Data>
</EventData>
</Event>
Required Server Roles: Active Directory domain controller.
Minimum OS Version: Windows Server 2008.
Event Versions: 0.
Field Descriptions:
- Destination DRA [Type = UnicodeString]: destination directory replication agent distinguished name.
Note The Directory Replication Agent (DRA) handles replication between domain controllers. The Directory Replication Agent uses the connection objects in the topology map to find out those partners that are relevant when replicating changes to directory partitions. The DRA sends a replication request to the partners of a domain controller when the domain controller needs to update its copy of Active Directory.
- Source DRA [Type = UnicodeString]: source directory replication agent distinguished name.
Note The LDAP API references an LDAP object by its distinguished name (DN). A DN is a sequence of relative distinguished names (RDN) connected by commas.
An RDN is an attribute with an associated value in the form attribute=value; . These are examples of RDNs attributes:
• DC - domainComponent
• CN - commonName
• OU - organizationalUnitName
• O - organizationName
Source Address [Type = UnicodeString]: DNS record of the server from which the “remove” request was received.
Naming Context [Type = UnicodeString]: naming context that was removed.
Note The Directory Tree of Active Directory tree is partitioned to allow sections to be distributed (replicated) to domain controllers in different domains within the forest. Each domain controller stores a copy of a specific part of the directory tree, called a Naming Context also known as Directory Partition. Naming Context is replicated as a unit to other domain controllers in the forest that contain a replica of the same sub tree. A Naming Context is also called a Directory Partition.
Options [Type = UInt32]: decimal value of DRS Options.
Status Code [Type = UInt32]: if there are no issues or errors, the status code will be 0. If an error happened, you'll receive Failure event and Status Code won't be equal to “0”. You can check error code meaning here: https://msdn.microsoft.com/library/windows/desktop/ms681381(v=vs.85).aspx
Security Monitoring Recommendations
For 4929(S, F): An Active Directory replica source naming context was removed.
Monitor for Source Address field, because the source of the request must be authorized for this action. If you find any unauthorized DRA, you should trigger an event.
This event is typically used for Active Directory replication troubleshooting.