Nothing I do will connect my OC 9 server to AD LDAPS, I have had this same issue since server version 8 and today after upgrading to latest stable same issues
Steps to reproduce
1. Login as Admin user
2. goto admin/LDAP section
3. enter server info, user, password and click test base DN
Expected behaviour
connecting to my AD server should show a green tab at top
Actual behaviour
always get a yellow message that says lost connection to LDAP server
I can telnet from the OC server to my LDAPS server and it has a valid cert on it for LDAPS
Server configuration
Operating system: Ubuntu 14
Web server: Apache
Database: Mysql
PHP version: 5.5.9-1ubuntu4.21
ownCloud version (see ownCloud admin page): 9.0.8 stable
Updated from an older ownCloud or fresh install: upgraded from 8 but LDAP did not connect then either
Special configuration (external storage, external authentication, reverse proxy, server-side-encryption):
ownCloud log (data/owncloud.log)
here is a tail of the log
{"reqId":"2Y5iptyaoPVKQKk0Ok+8","remoteAddr":"x.x.x.x","app":"user_ldap","message":"Wiz: Attemping to Bind ","level":0,"time":"2017-04-19T21:40:39+00:00","method":"POST","url":"\/owncloud\/index.php\/apps\/user_ldap\/ajax\/wizard.php","user":"someusername"}
{"reqId":"2Y5iptyaoPVKQKk0Ok+8","remoteAddr":"x.x.x.x","app":"PHP","message":"ldap_bind(): Unable to bind to server: Can't contact LDAP server at \/var\/www\/owncloud\/apps\/user_ldap\/lib\/ldap.php#254","level":3,"time":"2017-04-19T21:40:39+00:00","method":"POST","url":"\/owncloud\/index.php\/apps\/user_ldap\/ajax\/wizard.php","user":"someusername"}
{"reqId":"2dNoYVbpN5Zzd6vSDWBC","remoteAddr":"x.x.x.x","app":"user_ldap","message":"Turned off SSL certificate validation successfully.","level":0,"time":"2017-04-19T21:40:39+00:00","method":"POST","url":"\/owncloud\/index.php\/apps\/user_ldap\/ajax\/testConfiguration.php","user":"someusername"}
{"reqId":"7M00GbslbPegtEEYIeXF","remoteAddr":"x.x.x.x","app":"user_ldap","message":"Count filter: objectclass=*","level":0,"time":"2017-04-19T21:41:50+00:00","method":"POST","url":"\/owncloud\/index.php\/apps\/user_ldap\/ajax\/wizard.php","user":"someusername"}
{"reqId":"7M00GbslbPegtEEYIeXF","remoteAddr":"x.x.x.x","app":"user_ldap","message":"Turned off SSL certificate validation successfully.","level":0,"time":"2017-04-19T21:41:50+00:00","method":"POST","url":"\/owncloud\/index.php\/apps\/user_ldap\/ajax\/wizard.php","user":"someusername"}
{"reqId":"605XLoc8yqwuQLG6JpFf","remoteAddr":"x.x.x.x","app":"PHP","message":"ldap_bind(): Unable to bind to server: Can't contact LDAP server at \/var\/www\/owncloud\/apps\/user_ldap\/lib\/ldap.php#254","level":3,"time":"2017-04-19T21:46:10+00:00","method":"POST","url":"\/owncloud\/index.php\/apps\/user_ldap\/ajax\/wizard.php","user":"someusername"}
{"reqId":"605XLoc8yqwuQLG6JpFf","remoteAddr":"x.x.x.x","app":"PHP","message":"ldap_bind(): Unable to bind to server: Can't contact LDAP server at \/var\/www\/owncloud\/apps\/user_ldap\/lib\/ldap.php#254","level":3,"time":"2017-04-19T21:46:10+00:00","method":"POST","url":"\/owncloud\/index.php\/apps\/user_ldap\/ajax\/wizard.php","user":"someusername"}
{"reqId":"605XLoc8yqwuQLG6JpFf","remoteAddr":"x.x.x.x","app":"PHP","message":"ldap_bind(): Unable to bind to server: Can't contact LDAP server at \/var\/www\/owncloud\/apps\/user_ldap\/lib\/ldap.php#254","level":3,"time":"2017-04-19T21:46:10+00:00","method":"POST","url":"\/owncloud\/index.php\/apps\/user_ldap\/ajax\/wizard.php","user":"someusername"}
{"reqId":"605XLoc8yqwuQLG6JpFf","remoteAddr":"x.x.x.x","app":"PHP","message":"ldap_bind(): Unable to bind to server: Can't contact LDAP server at \/var\/www\/owncloud\/apps\/user_ldap\/lib\/ldap.php#254","level":3,"time":"2017-04-19T21:46:10+00:00","method":"POST","url":"\/owncloud\/index.php\/apps\/user_ldap\/ajax\/wizard.php","user":"someusername"}
{"reqId":"605XLoc8yqwuQLG6JpFf","remoteAddr":"x.x.x.x","app":"PHP","message":"ldap_bind(): Unable to bind to server: Can't contact LDAP server at \/var\/www\/owncloud\/apps\/user_ldap\/lib\/ldap.php#254","level":3,"time":"2017-04-19T21:46:10+00:00","method":"POST","url":"\/owncloud\/index.php\/apps\/user_ldap\/ajax\/wizard.php","user":"someusername"}
Please paste possible errors in the following code block, see https://central.owncloud.org/t/how-to-find-webserver-or-oc-logfile-enable-php-logfile/808 for more info
Integrity status for oC9+
Login as admin user into your ownCloud and access
http://example.com/index.php/settings/integrity/failed
no errors found