One of the searches Hudson does on LDAP is to locate the user record given the user name.

This field determines the query to be run to identify the user record. The query is almost always `"uid={0}"` as per defined in RFC 2798, so in most cases you should leave this field empty and let this default kick in.

If your LDAP server doesn't have uid or doesn't use a meaningful uid value, try `"mail={0}"`, which lets people login by their e-mail address.

If you do specify a different query, specify an LDAP query string with marker token "{0}", which is to be replaced by the user name string entered by the user.