SMTP Proxy to Office 365

The configuration you have provided seems to be a virtual server configuration for SMTP proxying to smtp.office365.com. However, it appears that you are encountering an issue with STARTTLS not being supported by the server.

To enable STARTTLS for your SMTP proxy, you may need to add a configuration to negotiate TLS encryption with the destination server. Here's an updated configuration snippet that includes the STARTTLS option:

perl
Copy code
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 {
context serverside
}
tcp {
context serverside
}
starttls {
context serverside
}
}
serverssl-use-sni disabled
source 0.0.0.0/0
source-address-translation {
type automap
}
translate-address enabled
translate-port enabled
vs-index 12
}
By adding the starttls profile under profiles, the SMTP proxy will attempt to negotiate a TLS connection using STARTTLS with the destination server.

Note: Ensure that you have the necessary SSL certificate configurations in place and that your proxy server is capable of handling the TLS negotiation and encryption process.

Please note that this is a simplified example, and you may need to further customize the configuration based on your specific environment and requirements.

Regards,

O365CloudExperts.