Login SVN2230 SSL VPN failed by using AD server

The customer uses SVN2230 as the VPN gateway, when the customer logins SSL VPN by using AD server to authenticate, but always failed.

Topology:

The information is shown as following:

Error：Administrator binding failed.

The checked steps as following:

(1)  Firstly, check the connectivity of network between SVN2230 and AD server, After do ping test, the result is reachable.

(2) After that , check the configuration of LDAP server template in SVN2230.I find that the "Administrator DN" is configured as full DN name(the name include base DN), At the same time, the "Bind attributes to Administrator" is open yet. If configured like this, the administrator account will be incorrect. So the authentication will be failed. The configuration is shown as following:

According to the error information, the probable reasons as following:
（1） There are some incorrect configuration for AD authentication in SVN2230;
（2） The account or password which used is incorrect;
（3） The network between SVN2230 and AD server is unreachable;

Because of the incorrect configuration of LDAP server template, the administrator account will be incorrect and the authentication will be failed.

Suggestion:
When configure AD server authenticaiton, please check if "Administrator DN" is configured as full DN name, if it is, please don't open "Bind attributes to Administrator", if not, please open .