SMTP Proxy to Office 365
I'm trying to setup a proxy for SMTP going to smtp.office365.com. I've searched for SMTP documentation, the only one I've come across is quite dated with a version cap of 13.0. But using this as a reference I've come up with a basic config.
So far, the only connection I've been able to get to o365 is with a client SSL profile, and the default SMTPS profile. Unfortunately this always ends with the server (o365 smtp) replying back with STARTTLS is required to send mail. Running the same test to smtp.office365.com directly works as it should.
ltm virtual smtp.example.com_587 {
creation-time 2022-01-12:11:16:46
destination 10.0.0.12:submission
ip-protocol tcp
last-modified-time 2022-01-13:16:47:35
mask 255.255.255.255
pool smtp.office365.com_587
profiles {
smtp.example.com {
context clientside
}
smtps { }
tcp { }
}
serverssl-use-sni disabled
source 0.0.0.0/0
source-address-translation {
type automap
}
translate-address enabled
translate-port enabled
vs-index 12
}
The pool for this has quite a few members and is a bit long to list here. The members are simply the FQDN of smtp.office365.com
The reason behind a setup this way is to prevent having an SMTP server locally, but allowing things that don't normally have internet access the ability to send email.