OpenLDAP Chain not found

Solution 1:

The Chain overlay is loaded via the back_ldap module. This is achieved by using:

ldapadd -Y EXTERNAL -H ldapi:///

then paste:

dn: cn=module{0},cn=config
changetype: modify
add: olcModuleLoad
olcModuleLoad: back_ldap

After a restart of slapd, the required schemas, such as olcChainConfig, will be availablie

A good Chain LDIF example is given here: https://stackoverflow.com/a/15972631/1554386