[Samba] Stalled Replication & "DsGetNCChanges 2nd replication"

[Adam Tauno Williams]

I am attempting to add a Windows 2008R2 DC to my S4 domain... and it  
always stalls out attempting to replicate CN=Configuration object X of  
Y.   So I have been digging, digging, digging, and I found this in the  
log file of the DC the 2008R2 box is attempting to replicate from -

Feb  1 16:52:42 larkin28 samba[18650]:    
../source4/rpc_server/drsuapi/getncchanges.c:1961: DsGetNCChanges 2nd  
replication on DN CN=Configuration,DC=micore,DC=us older highwatermark  
(last_dn CN=414,CN=DisplaySpecifiers,CN=Configuration,DC=micore,DC=us)
Feb  1 16:52:44 larkin28 samba[18650]: [2017/02/01 16:52:44.553389,   
0]  
../source4/rpc_server/drsuapi/getncchanges.c:1961(dcesrv_drsuapi_DsGetNCChanges)
Feb  1 16:52:44 larkin28 samba[18650]:    
../source4/rpc_server/drsuapi/getncchanges.c:1961: DsGetNCChanges 2nd  
replication on DN CN=Configuration,DC=micore,DC=us older highwatermark  
(last_dn CN=414,CN=DisplaySpecifiers,CN=Configuration,DC=micore,DC=us)
Feb  1 16:53:33 larkin28 samba[18650]: [2017/02/01 16:53:33.282166,   
0]  
../source4/rpc_server/drsuapi/getncchanges.c:1961(dcesrv_drsuapi_DsGetNCChanges)
Feb  1 16:53:33 larkin28 samba[18650]:    
../source4/rpc_server/drsuapi/getncchanges.c:1961: DsGetNCChanges 2nd  
replication on DN CN=Configuration,DC=micore,DC=us older highwatermark  
(last_dn CN=414,CN=DisplaySpecifiers,CN=Configuration,DC=micore,DC=us)
Feb  1 16:53:47 larkin28 samba[18650]: [2017/02/01 16:53:47.394951,   
0]  
../source4/rpc_server/drsuapi/getncchanges.c:1961(dcesrv_drsuapi_DsGetNCChanges)
Feb  1 16:53:47 larkin28 samba[18650]:    
../source4/rpc_server/drsuapi/getncchanges.c:1961: DsGetNCChanges 2nd  
replication on DN CN=Configuration,DC=micore,DC=us older highwatermark  
(last_dn CN=414,CN=DisplaySpecifiers,CN=Configuration,DC=micore,DC=us)
Feb  1 16:54:09 larkin28 samba[18650]: [2017/02/01 16:54:09.015323,   
0]  
../source4/rpc_server/drsuapi/getncchanges.c:1961(dcesrv_drsuapi_DsGetNCChanges)

This goes on and on and on with this object.

To anyone who knows more than me does this look like a possible source  
of the problem?

And what is "CN=414,CN=DisplaySpecifiers,..."?  It seems to have  
something to do with Exchange.

[root at larkin28 samba]# ldbsearch --extended-dn --reveal --cross-ncs -H  
/var/lib/samba/private/sam.ldb  --show-recycled  --show-deleted -s sub  
CN=414
dn:  
<GUID=8a714d09-a31c-4a1d-9e6b-4522fbd55da9>;CN=414,CN=DisplaySpecifiers,CN=Configuration,DC=micore,DC=us
objectClass: top
objectClass: container
cn: 414
instanceType: 4
whenCreated: 20121215005505.0Z
whenChanged: 20121215005505.0Z
uSNCreated: 1663
showInAdvancedViewOnly: TRUE
name: 414
objectGUID: 8a714d09-a31c-4a1d-9e6b-4522fbd55da9
objectCategory: <GUID=5796590e-095c-4a74-8f75-479bef316615>;CN=Container,CN=Sc
  hema,CN=Configuration,DC=micore,DC=us
uSNChanged: 286105
distinguishedName: <GUID=8a714d09-a31c-4a1d-9e6b-4522fbd55da9>;CN=414,CN=Displ
  aySpecifiers,CN=Configuration,DC=micore,DC=us