Hello everybody,
I'm using OpenLdap version 2.4.24  (4 Oct 2011) on a RedHat 6 machine. I use dynamic configuration and I'm having some problems setting up accesslog overlay. I didn't change the following file in etc/openldap/slapd.d/cn=config/ :
olcDatabase={-1}frontend.ldif
olcDatabase={0}config.ldif
olcDatabase={1}monitor.ldif

I moved olcDatabase={2}bdb.ldif to olcDatabase={3}bdb.ldif, in this way it is loaded after the access log database that is defined in the new olcDatabase={2}bdb.ldif

Here there are the two configuration files:

######### olcDatabase={2}bdb.ldif ###############
dn: olcDatabase={2}bdb
objectClass: olcDatabaseConfig
objectClass: olcBdbConfig
olcDatabase: {2}bdb
olcDbDirectory: /var/lib/ldap/accesslog/
olcSuffix: cn=accesslog
olcAccess: {0}to dn.subtree="cn=accesslog" by dn.exact="uid=manager,ou=Users,dc=domain,dc=com" manage by dn.exact="cn=config" read
olcLastMod: TRUE
olcMaxDerefDepth: 15
olcReadOnly: FALSE
olcRootDN: cn=accesslog
olcSizeLimit: unlimited
olcTimeLimit: unlimited
olcMonitoring: TRUE
olcDbCacheSize: 10000
olcDbCheckpoint: 64 5
olcDbNoSync: FALSE
olcDbDirtyRead: FALSE
olcDbIDLcacheSize: 10000
olcDbIndex: entryCSN eq
olcDbIndex: objectClass eq
olcDbIndex: reqEnd eq
olcDbIndex: reqResult eq
olcDbIndex: reqStart eq
olcDbLinearIndex: FALSE
olcDbMode: 0600
olcDbSearchStack: 16
olcDbShmKey: 0
olcDbCacheFree: 1
olcDbDNcacheSize: 0

######### olcDatabase={3}bdb.ldif ###############
dn: olcDatabase={3}bdb
objectClass: olcDatabaseConfig
objectClass: olcBdbConfig
olcDatabase: {3}bdb
olcSuffix: dc=domain,dc=com
olcAddContentAcl: FALSE
olcLastMod: TRUE
olcMaxDerefDepth: 15
olcReadOnly: FALSE
olcRootDN: cn=Manager, dc=domain,dc=com
olcRootPW: pippopippo
olcSyncUseSubentry: FALSE
olcMonitoring: TRUE
olcDbDirectory: /var/lib/ldap
olcDbCacheSize: 1000
olcDbCheckpoint: 1024 15
olcDbNoSync: FALSE
olcDbDirtyRead: FALSE
olcDbIDLcacheSize: 0
olcDbIndex: objectClass pres,eq
olcDbIndex: cn pres,eq,sub
olcDbIndex: uid pres,eq,sub
olcDbIndex: uidNumber pres,eq
olcDbIndex: gidNumber pres,eq
olcDbIndex: mail pres,eq,sub
olcDbIndex: ou pres,eq,sub
olcDbIndex: loginShell pres,eq
olcDbIndex: sn pres,eq,sub
olcDbIndex: givenName pres,eq,sub
olcDbIndex: memberUid pres,eq,sub
olcDbIndex: nisMapName pres,eq,sub
olcDbIndex: nisMapEntry pres,eq,sub
olcDbIndex: entryCSN eq
olcDbIndex: entryUUID eq
olcDbLinearIndex: FALSE
olcDbMode: 0600
olcDbSearchStack: 16
olcDbShmKey: 0
olcDbCacheFree: 1
olcDbDNcacheSize: 0
structuralObjectClass: olcBdbConfig
entryUUID: 9ef24df8-376a-1031-947f-692d47ac0213
creatorsName: cn=config
createTimestamp: 20120521082800Z
entryCSN: 20120521082800.652940Z#000000#000#000000
modifiersName: cn=config
modifyTimestamp: 20120521082800Z
olcOverlay: syncprov
olcSpCheckpoint: 50 10
olcSpSessionlog: 100
olcOverlay: accesslog
olcAccessLogDB: cn=accesslog
olcAccessLogOps: writes
olcAccessLogSuccess: TRUE
olcAccessLogPurge: 07+00:00 01+00:00

When I run slapd -d 1 I obtain the following error that makes slapd to terminate:

backend_startup_one: starting "cn=accesslog"
bdb_db_open: warning - no DB_CONFIG file found in directory /var/lib/ldap/accesslog/: (2).
Expect poor performance for suffix "cn=accesslog".
bdb_db_open: database "cn=accesslog": dbenv_open(/var/lib/ldap/accesslog/).
backend_startup_one: starting "dc=domain,dc=com"
bdb_db_open: warning - no DB_CONFIG file found in directory /var/lib/ldap: (2).
Expect poor performance for suffix "dc=domain,dc=com".
bdb_db_open: database "dc=domain,dc=com": dbenv_open(/var/lib/ldap).
accesslog: "logdb <suffix>" missing or invalid.
backend_startup_one (type=bdb, suffix="dc=domain,dc=com"): bi_db_open failed! (1)
slapd shutdown: initiated

It seems that for some reason slapd doesn't like the olcAccessLogDB directive specified in olcDatabase={3}bdb.ldif. I tried some other configuration (I think that this is the more correct) but the problem is always there. 

Thanks for any help,
Francesco