Event ID: 30021 , Event ID: 30027

In a multi domain environment if you have not configured every domain in the forest for OCS or LCS, you can expect these errors in the event viewer.

---------------------------------------------------------------
Event Type: Information
Event Source: OCS User Replicator
Event Category: (1009)
Event ID: 30021
Date:
Time:
User: N/A
Computer: OCS
Description:
User Replicator connected to domain controller dc.ocsdom.local in domain ocsdom.local to perform synchronization

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
---------------------------------------------------------------

Event Type: Information
Event Source: OCS User Replicator
Event Category: (1009)
Event ID: 30027
Date:
Time:
User: N/A
Computer: OCS
Description:
User Replicator has started initial synchronization of domain ocsdom.local (DN: DC=OCSDOM,DC=Local) and the database. Initial synchronization occurs when Office Communications Server is started for the first time, or a regenerate operation is initiated.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
 

 

Solution:

LCS or OCS is only configured for some domains in the forest. The User Replicator events are occurring for other domains in the forest which do not have LCS or OCS installed and have not had been configured with LCS or OCS  "Domain Add".

The User Replicator is trying to synchronize every LCS or OCS enabled user or contact object in Active Directory forest with all domains in the forest it has been deployed in.
 

Steps to resolve the issue:

You can work-around this issue via changing either the User Replicator polling
interval or changing the domains polled by the User Replicator using the information
below.


Change Polling Interval using WMI:

The default polling frequency for User Replicator is 60 seconds. This means that
every 60 seconds, User Replicator will ask Active Directory for any changes that
have happened to user objects in the last 60 seconds. This frequency is
configurable. Generally speaking, configuring this value to be something other than
the default is not necessary since the network overhead of the LDAP traffic that
User Replicator causes is so low. However, in some cases, such as with a very slow
or bandwidth sensitive link that User Replicator is synchronizing across, it may
make sense for administrators to change this interval. This interval is a per pool
value and can be set by WMI.(ReplicationCycleInterval attribute of
MSFT_SIPUserReplicatorSetting WMI class).

Here are the steps for changing this using wbemtest.exe tool:
1. Click Start, click Run, and then type wbemtest.exe
2. In the Windows Management Instrumentation (WMI) Tester dialog box, click
Connect.
3. In the Namespace box, type: root\cimv2
4. Click Connect.
5. Click Enum Instances
6. In the Enter Superclass name box, type: MSFT_SIPUserReplicatorSetting
7. Click OK
8. In the Query Result dialog box, double click the resulted instance
9. In the Object editor for MSFT_SIPUserReplicatorSetting dialog box, under Update
type, select the radio button: Update only
10. In the Object editor for MSFT_SIPUserReplicatorSetting dialog box, select
ReplicationCycleInterval from the Properties list and click Edit Property
11. In the Property Editor dialog box, under Value, select Not Null and enter the
value: 30
12. Click Save Property
13. In the Object editor for MSFT_SIPUserReplicatorSetting dialog box, click Save
Object
14. Click Exit to exit from Windows Management Instrumentation (WMI) Tester dialog
box


Configure User Replicator so that it only connects to the domains that have SIP
users in them using a WMI script:

By default, User Replicator operates in a zero configuration mode in which it
attempts to synchronize all domains in the forest that it has been deployed in. For
forests with one or two domains in which both domains have LCS or OCS enabled user
objects, this mode is fine. However, if the forest has many domains and only one
domain has LCS or OCS enabled user objects, this can result in a lot of superfluous
events being logged by User Replicator because it won't have access to those
domains. In that case, administrators can set up a list of domains that User
Replicator will only pull from. This list is set via WMI (UserDomainList attribute
of MSFT_SIPESGlobalRegistrarSetting WMI class).

Below is a sample WMI script that can be used to modify this setting:

Dim ObjGlobalSetting
Dim objWbem
Dim DomainList

' DomainList has a list of domains that tells UR which domains to sync.
' In this sample we are setting it up to sync domains domain1.fabrikam.com and
domain2.fabrikam.com

DomainList =
array("DC=domain1,DC=fabrikam,DC=com","DC=domain2,DC=fabrikam,DC=com")

set objWbem=
CreateObject("WbemScripting.SWbemLocator").ConnectServer(".","root\cimv2")

for each ObjGlobalSetting in objWbem.ExecQuery("select * from
MSFT_SIPESGlobalRegistrarSetting")

ObjGlobalSetting.UserDomainList = DomainList
ObjGlobalSetting.Put_ 1

next


Below is a sample WMI script that can be used to view this setting:

Dim ObjGlobalSetting
Dim objWbem
Dim DomainList
Dim i

set objWbem=
CreateObject("WbemScripting.SWbemLocator").ConnectServer(".","root\cimv2")
for each ObjGlobalSetting in objWbem.ExecQuery("select * from
MSFT_SIPESGlobalRegistrarSetting")
DomainList = ObjGlobalSetting.UserDomainList
next

Wscript.echo "Verifying the value set for
MSFT_SIPESGlobalRegistrarSetting::UserDomainList"
Wscript.echo
"------------------------------------------------------------------------"

i = 1
for each domain in DomainList
wscript.echo "Domain " & i & ": " & domain
i = i + 1
next