Cisco Cisco Email Security Appliance C680 User Guide

The variable names you enter for queries are case-sensitive and must match your LDAP implementation 
in order to work correctly. For example, entering 

 at a prompt performs a different 

query than entering 

. Cisco IronPort Systems strongly recommends using the 

test

 

subcommand of the 

ldapconfig

 command to test all queries you construct and ensure the proper results 

are returned. 

If the LDAP server is unreachable by the appliance, one of the following errors will be shown:

Error: LDAP authentication failed: <LDAP Error "invalidCredentials" [0x31]> 

Error: Server unreachable: unable to connect

 

Error: Server unreachable: DNS lookup failure

 

Note that a server may be unreachable because the wrong port was entered in the server configuration, 
or the port is not opened in the firewall. LDAP servers typically communicate over port 3268 or 389. 
Active Directory uses port 3268 to access the global catalog used in multi-server environments (See 
“Firewall Information” in the Cisco IronPort AsyncOS for Email Configuration Guide for more 
information.) In AsyncOS 4.0, the ability to communicate to the LDAP server via SSL (usually over port 
636) was added. For more information, see 

.

A server may also be unreachable because the hostname you entered cannot be resolved.

You can use the Test Server(s) on the Add/Edit LDAP Server Profile page (or the 

test

 subcommand of 

the 

ldapconfig

 command in the CLI) to test the connection to the LDAP server. For more information, 

see 

If the LDAP server is unreachable:

If LDAP Accept or Masquerading or Routing is enabled on the work queue, mail will remain within 
the work queue.

If LDAP Accept is not enabled but other queries (group policy checks, etc.) are used in filters, the 
filters evaluate to false.

You can use your existing LDAP infrastructure to define how the recipient email address of incoming 
messages (on an public listener) should be handled. Changes to user data in your directories are updated 
the next time the Cisco IronPort appliance queries the directory server. You can specify the size of the 
caches and the amount of time the Cisco IronPort appliance stores the data it retrieves.

You may wish to bypass LDAP acceptance queries for special recipients (such as 

administrator@example.com

). You can configure this setting from the Recipient Access Table (RAT). 

For information about configuring this setting, see “Configuring the Gateway to Receive Email” in the 
Cisco IronPort AsyncOS for Email Configuration Guide.