Replication delay

[Ángel L. Mateo <amateo@um.es>]

Hello,

	I've been running a multi master configuration without any problem for 
years. This running servers are running in 5 ubuntu 14.04 servers with 
openldap 2.4.43.

	The configuration is:

dn: olcDatabase={3}mdb,cn=config
...
olcSyncrepl: {0}rid=31 provider=ldap://canis31.um.es binddn=<repl user 
dn> bindmethod=simple credentials=XXXXXXX searc
 hbase=dc=Telematica type=refreshAndPersist retry="300 +" timeout=1
olcSyncrepl: {1}rid=32 provider=ldap://canis32.um.es binddn=<repl user 
dn> bindmethod=simple credentials=XXXXXXX searc
 hbase=dc=Telematica type=refreshAndPersist retry="300 +" timeout=1
olcSyncrepl: {2}rid=33 provider=ldap://canis33.um.es binddn=<repl user 
dn> bindmethod=simple credentials=XXXXXXX searc
 hbase=dc=Telematica type=refreshAndPersist retry="300 +" timeout=1
olcSyncrepl: {3}rid=34 provider=ldap://canis34.um.es binddn=<repl user 
dn> bindmethod=simple credentials=XXXXXXX searc
 hbase=dc=Telematica type=refreshAndPersist retry="300 +" timeout=1

dn: olcOverlay={0}dynlist,olcDatabase={3}mdb,cn=config
objectClass: olcDynamicList
objectClass: olcOverlayConfig
objectClass: olcConfig
olcOverlay: {0}dynlist
olcDlAttrSet: {0}labeledURIObject labeledURI

dn: olcOverlay={1}ppolicy,olcDatabase={3}mdb,cn=config
objectClass: olcPPolicyConfig
objectClass: olcOverlayConfig
objectClass: olcConfig
olcOverlay: {1}ppolicy
olcPPolicyDefault: cn=default,ou=policies,dc=Telematica

dn: olcOverlay={2}syncprov,olcDatabase={3}mdb,cn=config
objectClass: olcSyncProvConfig
objectClass: olcOverlayConfig
objectClass: olcConfig
olcOverlay: {2}syncprov
olcSpCheckpoint: 100 10
olcSpSessionlog: 100

	where each server has 4 olcSyncrepl attributes pointing to the other 
servers.

	I had no problem with this configuration for years

	Now I'm deploying an update of these servers in a new ubuntu 18.04 
server with openldap 2.4.47. In order to synchronize entries between 
them, I have linked this new server to one of the other (and this one to 
the new one).

	Configuration in the new one (named canis41) is:

dn: olcDatabase={3}mdb,cn=config
...
olcSyncrepl: {0}rid=39 provider=ldap://canis39.um.es binddn=<repl user 
dn> bindmethod=simple credentials=XXXXXXXX searc
 hbase=dc=Telematica type=refreshAndPersist retry="60 +" timeout=1 
schemache
 cking=off scope=sub
olcSyncrepl: {1}rid=42 provider=ldap://canis42.um.es binddn=<repl user 
dn> bindmethod=simple credentials=XXXXXXXX searc
 hbase=dc=Telematica type=refreshAndPersist retry="30 +" timeout=1 
logbase="
 cn=log" logfilter="(&(objectClass=auditWriteObject)(reqResult=0))" 
schemaCh
 ecking=on syncdata=accesslog exattrs="pwdFailureTime"

dn: olcOverlay={0}syncprov,olcDatabase={3}mdb,cn=config
objectClass: olcSyncProvConfig
objectClass: olcOverlayConfig
objectClass: olcConfig
olcOverlay: {0}syncprov
olcSpCheckpoint: 100 10
olcSpSessionlog: 100

dn: olcOverlay={1}ppolicy,olcDatabase={3}mdb,cn=config
objectClass: olcPPolicyConfig
objectClass: olcOverlayConfig
objectClass: olcConfig
olcOverlay: {1}ppolicy
olcPPolicyDefault: cn=default,ou=policies,dc=Telematica

dn: olcOverlay={2}dynlist,olcDatabase={3}mdb,cn=config
objectClass: olcDynamicList
objectClass: olcOverlayConfig
objectClass: olcConfig
olcOverlay: {2}dynlist
olcDlAttrSet: {0}labeledURIObject labeledURI

	where canis39 is one the former servers and canis42 is a new server too 
synchronizing just with canis41.

	My problem is that synchronization is working, but sometimes 
modifications done in the canis3x farm are delayed a lot of time until 
they are replicated to the new one (sometimes in the order of 40-60 
minutes).

	I'm logging sync logs, but I haven't found much information about these 
logs. Is there any way to debug it? How?

--
Angel L. Mateo Martínez
Sección de Telemática
Área de Tecnologías de la Información
y las Comunicaciones Aplicadas (ATICA)
http://www.um.es/atica
Tfo: 868889150
Fax: 868888337