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STARTTLS Server SMTP with cleartext and STARTTLS client support

Problem this snippet solves: We were looking at our O365 security score and our SMTP scores were pretty sad, so I looked at how I could create a STARTTLS connection up to O365 regardless of the clie...
Published May 02, 2019
Version 1.0
devops
iRules
LTM
smtp
Sam_Novak's avatar
Sam_Novak
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Sep 17, 2019

 

 

The issue I run into with SMTPS is that the LTM logs complain about not having a forward proxy license, and when I attempt to send messages to it I get an '01260009:4: Connection error: hud_ssl_handler:1170: invalid profile (40)'. Additionally, when I attempt to configure the iApp, I also get an error message regarding ssl forward proxy not being enabled. I believe this is part of SSL Orchestrator, but I do not have a license for that (which is funny because I have 1Gb VE Best).

 

And I guess an added benefit of doing this in an iRule is that I can get some logging about what messages are sent, which I send over to Elasticsearch. That's already proven to be very handy as we transition to LTM with my iRule for compatibility with Office 365 relaying.