error message "The Knowledge Consistency Checker (KCC) was unable to form a complete spanning tree network topology"

I have 4 domains controllers in a domain under windows 2003 (DR01, DC01, DC02, DC03,) and i meet problem when replicating from DC01, DC02 to DR01

The replication From DC03 To other DCs is fine. I think I have problem with DR01 DC.

Would be much appreciated if anyone can give a clue on this?

root.local = root domain
us.root.local = parent domain
domain1.us.root.local = child domain
domain2.us.root.local = child domain
domain3.us.root.local = child domain

all below DCs are under us.root.local domain

DR01 - Windows 2003 Server Enterprise Edition SP2
DC01 - Windows 2003 Server STD Edition SP2
DC02 - Windows 2003 Server STD Edition SP2
DC03 - Windows 2003 Server STD Edition SP2

I see below error logs on DR01 server.
=======================================

Event Type: Warning
Event Source: NTDS KCC
Event Category: Knowledge Consistency Checker
Event ID: 1865
Date: 9/1/2011
Time: 3:50:37 AM
User: NT AUTHORITY\ANONYMOUS LOGON
Computer: DR01
Description:
The Knowledge Consistency Checker (KCC) was unable to form a complete spanning tree network topology. As a result, the following list of sites cannot be

reached from the local site.

Sites:
CN=ST_US_EGC002,CN=Sites,CN=Configuration,DC=root,DC=local

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

Event Type: Error
Event Source: NTDS KCC
Event Category: Knowledge Consistency Checker
Event ID: 1311
Date: 9/1/2011
Time: 3:50:37 AM
User: NT AUTHORITY\ANONYMOUS LOGON
Computer: DR01
Description:
The Knowledge Consistency Checker (KCC) has detected problems with the following directory partition.

Directory partition:
CN=Configuration,DC=root,DC=local

There is insufficient site connectivity information in Active Directory Sites and Services for the KCC to create a spanning tree replication topology. Or,

one or more domain controllers with this directory partition are unable to replicate the directory partition information. This is probably due to

inaccessible domain controllers.

User Action
Use Active Directory Sites and Services to perform one of the following actions:
- Publish sufficient site connectivity information so that the KCC can determine a route by which this directory partition can reach this site. This is the

preferred option.
- Add a Connection object to a domain controller that contains the directory partition in this site from a domain controller that contains the same directory

partition in another site.

If neither of the Active Directory Sites and Services tasks correct this condition, see previous events logged by the KCC that identify the inaccessible

domain controllers.

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

Event Type: Warning
Event Source: NTDS KCC
Event Category: Knowledge Consistency Checker
Event ID: 1566
Date: 9/1/2011
Time: 3:50:37 AM
User: NT AUTHORITY\ANONYMOUS LOGON
Computer: DR01
Description:
All domain controllers in the following site that can replicate the directory partition over this transport are currently unavailable.

Site:
CN=ST_US_EGC002,CN=Sites,CN=Configuration,DC=root,DC=local
Directory partition:
CN=Configuration,DC=root,DC=local
Transport:
CN=IP,CN=Inter-Site Transports,CN=Sites,CN=Configuration,DC=root,DC=local

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

==============================
Event Type: Warning
Event Source: NtFrs
Event Category: None
Event ID: 13508
Date: 8/2/2011
Time: 10:07:55 PM
User: N/A
Computer: DR01
Description:
The File Replication Service is having trouble enabling replication from DC02 to DR01 for d:\windows\sysvol\domain using the DNS name

DC02.domain2.us.root.local. FRS will keep retrying.
Following are some of the reasons you would see this warning.

[1] FRS can not correctly resolve the DNS name DC02.domain2.us.root.local from this computer.
[2] FRS is not running on DC02.domain2.us.root.local.
[3] The topology information in the Active Directory for this replica has not yet replicated to all the Domain Controllers.

This event log message will appear once per connection, After the problem is fixed you will see another event log message indicating that the connection has

been established.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
Data:
0000: ba 06 00 00 º...

=============================
Event Type: Warning
Event Source: NtFrs
Event Category: None
Event ID: 13508
Date: 8/25/2011
Time: 6:10:32 AM
User: N/A
Computer: DR01
Description:
The File Replication Service is having trouble enabling replication from DC01 to DR01 for d:\windows\sysvol\domain using the DNS name

DC01.domain2.us.root.local. FRS will keep retrying.
Following are some of the reasons you would see this warning.

[1] FRS can not correctly resolve the DNS name DC01.domain2.us.root.local from this computer.
[2] FRS is not running on DC01.domain2.us.root.local.
[3] The topology information in the Active Directory for this replica has not yet replicated to all the Domain Controllers.

This event log message will appear once per connection, After the problem is fixed you will see another event log message indicating that the connection has

been established.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
Data:
0000: d9 06 00 00 Ù...
============================

Ipconfig /all details of DR01 DC-

C:\>ipconfig /all

Windows IP Configuration

Host Name . . . . . . . . . . . . : DR01
Primary Dns Suffix . . . . . . . : domain2.us.root.local
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No
DNS Suffix Search List. . . . . . : domain2.us.root.local
root.com
domain1.us.root.local
eu.root.local
ecl.jp.root.local
domain3.us.root.local
ell.eu.root.local

Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : VMware Accelerated AMD PCNet Adapter
Physical Address. . . . . . . . . : 00-50-56-8E-3B-F4
DHCP Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 10.101.90.57
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 10.101.90.253
DNS Servers . . . . . . . . . . . : 10.101.80.35
10.101.180.231
Primary WINS Server . . . . . . . : 10.101.80.35
Secondary WINS Server . . . . . . : 10.101.180.231

==========================

IPconfig /all details of DC01

C:\>ipconfig /all

Windows IP Configuration

Host Name . . . . . . . . . . . . : dc01
Primary Dns Suffix . . . . . . . : domain2.us.root.local
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No
DNS Suffix Search List. . . . . . : domain2.us.root.local
root.com
domain1.us.root.local
eu.root.local
ecl.jp.root.local
domain3.us.root.local
ell.eu.root.local

Ethernet adapter Team/Production:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : BASP Virtual Adapter
Physical Address. . . . . . . . . : 00-21-5E-64-89-B4
DHCP Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 10.101.180.231
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 10.101.180.254
DNS Servers . . . . . . . . . . . : 10.101.80.35
10.101.180.231
Primary WINS Server . . . . . . . : 10.101.80.35
Secondary WINS Server . . . . . . : 10.101.180.231

================================
IPconfig /all details of DC02

C:\>ipconfig /all

Windows IP Configuration

Host Name . . . . . . . . . . . . : dc02
Primary Dns Suffix . . . . . . . : domain2.us.root.local
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No
DNS Suffix Search List. . . . . . : domain2.us.root.local
root.com
domain1.us.root.local
eu.root.local
ecl.jp.root.local
domain3.us.root.local
ell.eu.root.local

Ethernet adapter Production Team:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : BASP Virtual Adapter
Physical Address. . . . . . . . . : 00-21-5E-64-8A-56
DHCP Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 10.101.188.231
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 10.101.188.254
DNS Servers . . . . . . . . . . . : 10.101.80.35
10.101.180.231
Primary WINS Server . . . . . . . : 10.101.80.35
Secondary WINS Server . . . . . . : 10.101.180.231

================================

IPconfig /all details of DC03

C:\>ipconfig /all

Windows IP Configuration

Host Name . . . . . . . . . . . . : dc03
Primary Dns Suffix . . . . . . . : domain2.us.root.local
Node Type . . . . . . . . . . . . : Hybrid
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No
DNS Suffix Search List. . . . . . : domain2.us.root.local
root.com
domain1.us.root.local
eu.root.local
ecl.jp.root.local
domain3.us.root.local
ell.eu.root.local
root.local

Ethernet adapter Team/Backup:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : BASP Virtual Adapter #2
Physical Address. . . . . . . . . : 00-14-5E-86-E4-33
DHCP Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 192.168.80.35
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . :
NetBIOS over Tcpip. . . . . . . . : Disabled

Ethernet adapter Team/Production:

Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : BASP Virtual Adapter
Physical Address. . . . . . . . . : 00-14-5E-86-E4-33
DHCP Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 10.101.80.35
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 10.101.80.253
DNS Servers . . . . . . . . . . . : 10.101.80.35
10.101.180.231
Primary WINS Server . . . . . . . : 10.101.80.35
Secondary WINS Server . . . . . . : 10.101.180.231

=============================