entryCSN is larger (later) in consumer node than in provider node

[Frank Luo]

All,

I am having a out-of sync situation now with some entries'  entryCSN
is larger (later) in consumer node than in provider node. So the
consumer never gets updated since it thinks it has the latest value.

provider:
entryCSN: 20160520164908.960158Z#000000#001#000000

consumer:
entryCSN: 20160521191401.646572Z#000000#000#000000

slapd.conf in consumer:

overlay syncprov
syncprov-checkpoint 100 10
syncprov-sessionlog 100
syncrepl      rid=003
              provider=ldap://server.u.edu
              bindmethod=simple
              binddn="cn=Manager,dc=u,dc=com"
              credentials=password
              searchbase="dc=u,dc=com"
              schemachecking=on
              type=refreshAndPersist
              retry="60 +"


Any hint about this?  Thanks a lot!

Frank