Showing results for 
Search instead for 
Did you mean: 

Iron port slow connection through firewall interface, data blanked out

James Simpson
Level 1
Level 1

Hi Alll

Installing a new pair of IronPort c170 appliances behind a ASA 5520 and currently getting blanked out response when connecting via telnet on port 25 to the outside interface.  Testing this internally there are no issues and the hostname is shown, but from the outside, response is very slow and some information is masked as xxxxxxx.

Going through the ASA, esmtp stateful packet inspection is removed and the IPS has already been ruled out.

Has anyone come accross this issue before. Please could you shine some light on this.

Many thanks

1 Reply 1

Andreas Mueller
Level 4
Level 4

Hello James,

when some of the information is masked, this means you still have SMTP fixup enabled on the ASA. I am not an expert on these devices, but here is an article on this topic that may be useful:

Article #1816: Why do we see XXXXXXXA after EHLO and "500 #5.5.1 command not recognized" after STARTTLS? Link:

Hope that helps.