When a change takes place in Active Directory, there is a builtin delay before
the other domain controllers are notified that replication needs to occur. This
holdback time prevents constant replication activity. It
determines the delay between the change to the Active Directory and first
replication partner notification. The default is 300 seconds, that is 5 minutes.
If this interval is set too high, directory consistency could be compromised.
Too many changes are accumulated before being replicated. It is probably best to
leave this setting alone, but if you need to increase the holdback interval to
optimize replication performance, you use the following hack:
Hive: HKEY_LOCAL_MACHINE
Key: SYSTEM\CurrentControlSet\Services\NTDS\Parameters
Name: Replicator Notify Pause After
Modify
Type: REG_DWORD
If you have broadband, Microsoft has a 2 hour series of Webcasts on Active
Directory Replication:
- Support WebCast: Active Directory Replication in Windows 2000,
Part 1. (48 minutes)
- Support WebCast: Active Directory Replication in Windows 2000,
Part 2. (30 minutes)
- Support WebCast: Active Directory Replication in Windows 2000,
Part 3. (20 minutes)
- Support WebCast: Active Directory Replication in Windows 2000,
Part 4. (30 minutes)
domain controller with changes doesn’t notify all replication partners at once.
Instead, it notifies the first replication partner and waits for 30 seconds by
default, then notifies the next partner, and so on. This prevents all
replication partners from requesting copies of the changes at the same time and
thus prevents overloading the network. This is the Replicator
Notify Pause Between DSAs parm and it can be modified using the following
hack:
Hive: HKEY_LOCAL_MACHINE
Key: SYSTEM\CurrentControlSet\Services\NTDS\Parameters
Name: Replicator Notify Pause Between
DSAs
Type: REG_DWORD
W2K sets the remote procedure call (RPC) replication port dynamically. For
debug purposes, you might want to manually set the port. You can use the
following hack:
Hive: HKEY_LOCAL_MACHINE
Key: SYSTEM\CurrentControlSet\Services\NTDS\Parameters
Name: TCP/IP Port
Type: REG_DWORD
Set to
the port you want to monitor. Reboot. Be sure to remove this registry key after
monitoring, or you will be compromising your security with a static RPC port.
The Knowledge Consistency Checker (KCC) manages connection objects for inter-
and intrasite replication. KCC runs every 15 minutes by default. To change this
time period use the following hack:
Hive: HKEY_LOCAL_MACHINE
Key: SYSTEM\CurrentControlSet\Services\NTDS\Parameters
Name: Repl topology update period
(secs)
Type: REG_DWORD
and set the value.
