Use these guidelines to determine if your site should configure the LDAP data cache:
If Calendar Server at your site accesses your master (or root) LDAP directory server directly with no delays in the availability of committed LDAP data, you don’t need to configure the LDAP data cache. Make sure that the local.ldap.cache.enable parameter is set to “no” (which is the default).
If your site has deployed a Master/Slave LDAP Configuration where Calendar Server accesses the master LDAP directory through a slave LDAP directory server, which in turn introduces a delay in the availability of committed LDAP data, configure the LDAP data cache to ensure that your end users have the most recent data.