I'm replicating both the config and backend databases between two boxes. Everything seems fine, but for some reason when I query them both for the contextCSN, the config database returns only one while the backend database returns two, as seen below:

## ldap1 replication config olcDatabase={0}config.ldif:olcSyncrepl: {0}rid=001 provider=ldap://ldap1.example.com binddn="cn=admin,cn=co olcDatabase={0}config.ldif- nfig" bindmethod=simple credentials="SECRET" searchbase="cn=config" type olcDatabase={0}config.ldif- =refreshAndPersist retry="5 10 300 15" timeout=1 olcDatabase={0}config.ldif:olcSyncrepl: {1}rid=002 provider=ldap://ldap2.example.com binddn="cn=admin,cn=co olcDatabase={0}config.ldif- nfig" bindmethod=simple credentials="SECRET" searchbase="cn=config" type olcDatabase={0}config.ldif- =refreshAndPersist retry="5 10 300 15" timeout=1 olcDatabase={1}hdb.ldif:olcSyncrepl: {0}rid=003 provider=ldap://ldap1.example.com binddn="cn=admin,dc=exa olcDatabase={1}hdb.ldif- mple,dc=com" bindmethod=simple credentials="SECRET" searchbase="dc=example, olcDatabase={1}hdb.ldif- dc=com" type=refreshAndPersist retry="5 10 300 15" timeout=1 olcDatabase={1}hdb.ldif:olcSyncrepl: {1}rid=004 provider=ldap://ldap2.example.com binddn="cn=admin,dc=exa olcDatabase={1}hdb.ldif- mple,dc=com" bindmethod=simple credentials="SECRET" searchbase="dc=example, olcDatabase={1}hdb.ldif- dc=com" type=refreshAndPersist retry="5 10 300 15" timeout=1

## ldap2 replication config olcDatabase={0}config.ldif:olcSyncrepl: {0}rid=001 provider=ldap://ldap1.example.com binddn="cn=admin,cn=co olcDatabase={0}config.ldif- nfig" bindmethod=simple credentials="SECRET" searchbase="cn=config" type olcDatabase={0}config.ldif- =refreshAndPersist retry="5 10 300 15" timeout=1 olcDatabase={0}config.ldif:olcSyncrepl: {1}rid=002 provider=ldap://ldap2.example.com binddn="cn=admin,cn=co olcDatabase={0}config.ldif- nfig" bindmethod=simple credentials="SECRET" searchbase="cn=config" type olcDatabase={0}config.ldif- =refreshAndPersist retry="5 10 300 15" timeout=1 olcDatabase={1}hdb.ldif:olcSyncrepl: {0}rid=003 provider=ldap://ldap1.example.com binddn="cn=admin,dc=exa olcDatabase={1}hdb.ldif- mple,dc=com" bindmethod=simple credentials="SECRET" searchbase="dc=example, olcDatabase={1}hdb.ldif- dc=com" type=refreshAndPersist retry="5 10 300 15" timeout=1 olcDatabase={1}hdb.ldif:olcSyncrepl: {1}rid=004 provider=ldap://ldap2.example.com binddn="cn=admin,dc=exa olcDatabase={1}hdb.ldif- mple,dc=com" bindmethod=simple credentials="SECRET" searchbase="dc=example, olcDatabase={1}hdb.ldif- dc=com" type=refreshAndPersist retry="5 10 300 15" timeout=1

## Query root@ldap1:~# ldapsearch -x -H ldap://localhost -D 'cn=admin,cn=config' -y /etc/ldap.secret -b 'cn=config' -s base -LL contextCSN; ldapsearch -x -H ldap://localhost -D 'cn=admin,dc=example,dc=com' -y /etc/ldap.secret -b 'dc=example,dc=com' -s base -LL contextCSN version: 1

dn: cn=config contextCSN: 20091012205437.323661Z#000000#001#000000

version: 1

dn: dc=example,dc=com contextCSN: 20100126210305.876171Z#000000#001#000000 contextCSN: 20091018205321.288716Z#000000#002#000000

I checked the documentation, but didn't see anything that clarified this behavior. I've also checked the logs, and there are no replication failures in them. So what is the reason for this? The only difference I can see between the config and backend is that the backend database has two overlays (autogroup and syncprov) and the config db has only one (syncprov), but that may just be an irrelevant coincidence. I would be most appreciative if somebody could shed some light on this for me. Thanks!

Respectfully, Ryan