Hi List, I have trouble with my fresh setup openLDAP Master/Slave sync. The slave stops syncing every few hours with the message shown below. If I restart the slave things start working again. I monitored the network connectivity between th hosts and there is no issue with that. Debug output running slapd -d 256 -d 128 5b23c9dc do_syncrep2: rid=001 (-1) Can't contact LDAP server 5b23c9dc do_syncrepl: rid=001 rc -1 retrying (4 retries left) /var/log/syslog Jun 15 16:14:52 ldap-server slapd[5178]: do_syncrep2: rid=001 (-1) Can't contact LDAP server Jun 15 16:14:52 ldap-server slapd[5178]: do_syncrepl: rid=001 rc -1 retrying (4 retries left) I'm running Ubuntu 16.04.4 openLDAP 2.4.42 (from Ubuntu repository) on both servers. I setup the sync using these LDIFs on the master. |dn: olcDatabase={||1||}mdb,cn=config| |changetype: modify| |delete: olcAccess| |olcAccess: {||0||}| |-| |add: olcAccess| |olcAccess: {||0||}to attrs=userPassword,shadowLastChange| |  ||by dn=||"cn=admin,dc=domain,dc=com"| |write| |  ||by dn=||"cn=replicator,dc=domain,dc=com"| |write| |  ||by self write| |  ||by anonymous auth| |  ||by * none| |-| |delete: olcAccess| |olcAccess: {||2||}| |-| |add: olcAccess| |olcAccess: {||2||}to *| |  ||by dn=||"cn=admin,dc=domain,dc=com"| |manage| |  ||by dn=||"cn=replicator,dc=domain,dc=com"| |manage| |  ||by self write| |  ||by anonymous auth| |  ||by users read| |dn: cn=module{||0||},cn=config| |changetype: modify| |add: olcModuleLoad| |olcModuleLoad: syncprov.la <https://confluence.2rioffice.com/display/SA/syncprov.la>| |dn: olcDatabase={||1||}mdb,cn=config| |changetype: modify| |add: olcDbIndex| |olcDbIndex: entryUUID,entryCSN eq| |dn: olcOverlay=syncprov,olcDatabase={||1||}mdb,cn=config| |changetype: add| |objectClass: olcOverlayConfig| |objectClass: olcSyncProvConfig| |olcOverlay: syncprov| On the Slave I imported these LDIFs |dn: cn=module{||0||},cn=config| |changetype: modify| |add: olcModuleLoad| |olcModuleLoad: syncprov.la <https://confluence.2rioffice.com/display/SA/syncprov.la>| |dn: olcDatabase={||1||}mdb,cn=config| |changetype: modify| |add: olcDbIndex| |olcDbIndex: entryUUID,entryCSN eq| |dn: olcDatabase={||1||}mdb,cn=config| |changetype: modify| |add: olcSyncRepl| |olcSyncRepl: rid=||001| |  ||provider=ldap:||//ldap-master.domain.com/ <https://confluence.2rioffice.com/display/SA/ldap-grev-ham-de.2rioffice.co... |  ||bindmethod=simple| |  ||binddn=||"cn=replicator,dc=domain,dc=com"| |  ||credentials=PASSWORD| |  ||searchbase=||"dc=domain,dc=com"| |  ||scope=sub| |  ||schemachecking=on| |  ||type=refreshAndPersist| |  ||retry=||"30 5 300 3"| |  ||interval=||00||:||00||:||00||:||30| |  ||starttls=yes| |  ||tls_reqcert=allow| I'm really new to openLDAP so please let me know how to provide additional Info if you need them. Thanks and best regards, Kai