El servidor de ldap estaba caido.

Si al intentar rearrancarlo dice:

[root@ldap ~]# /etc/init.d/ldap restart Parando slapd: [FALLÓ] Checking configuration files for slapd: slap_startup failed (test would succeed using the -u switch) [FALLÓ] stale lock files may be present in /var/lib/ldap [AVISO]

[root@ldap ~]# /usr/sbin/slapd_db_recover -v -h /var/lib/ldap

Y arranca sin problema.