Ever wonder what mail servers the top U.S. companies run? I found myself wondering what the top universities used a while back, and I just recently got curious as to what the Fortune 100 companies used as well. The results were quite interesting; it’s always fun to see what some of these admins put in their mail banners:
220 plgmler2.imr.gm.com ESMTP Sendmail GM Secure; Thu, 17 Aug 2006 23:23:21 -0500 220 mail11.disney.com Postfix EGGS and Butter 220 IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted 220 Medco - Ready 220 mailgate2.safeway.com ESMTP ***** SMTP Ready ***** 220 mail1.cat.com ESMTP Microsoft Exchange Internet Mail Service 5.5.2657.72) ready 220 Northrop Grumman Corporation Ready 220 mms01bas.mms.us.syntegra.com (IntraStore TurboSendmail) ESMTP Service ready 220 [220.127.116.11] ESMTP 220 wamu.com Proxy Server 220 fdsmail01.fds.com Microsoft ESMTP MAIL Service, Version: 5.0.2195.6713 ready at Fri, 18 Aug 2006 00:31:58 -0400Quite a few of the banners warn anyone reading not to use the service for spam, although I have to wonder whether or not a spammer has ever changed their behavior due to a warning like this.
We also get to see some personality in the way the servers say goodbye (SMTP 221):
221 Bye 221 Until later [18.104.22.168] 221 Catch you laterAnyway, here are the complete results as well as the stuff I used to run the test:
- There’s a fine line between being curious about interesting service banners and portscanning. If you don’t know what that difference is then you probably shouldn’t be doing this at home. :)