1
vote
3answers
4k views

How to configure sendmail to relay emails through Office 365 (SMTP) with TLS

I have a box running RHEL 6.3 and there's and application that needs to send out reports by mail, in order for this functionality to work I have to have mail configured in my box. In addition I ...
1
vote
1answer
194 views

Is it possible to configure sendmail to require/use certain ciphers during TLS negotiation?

CentOS 5.x | SendMail I'd like sendmail to use a specific cipher when negotiating a TLS session with a specific remote MTA/domain. Is that possible? I'm aware that a minimum bit strength can be ...
2
votes
1answer
2k views

After reading lots of articles on sendmail relay tls port 587 gmail, still having problems

Environment is Amazon EC2, running Amazon Linux (Centos-like) with sendmail 8.14.4 and Cyrus sasl 2.1.23. The machine has an elastic IP address that is the target of a domain name, and reverse DNS is ...
2
votes
2answers
467 views

Is there a way to completely disable outbound opportunistic TLS support in SendMail?

CentOS 5.x SendMail 8.14.4 An overzealous network security feature is causing TLS negotiations to fail when my Sendmail server tries to talk to external hosts. This is causing sendmail to constantly ...
2
votes
1answer
2k views

How to change sendmail fallback behavior if TLS handshake fails?

I have a CentOS 5.x server running sendmail that is failing to negotiate TLS with SOME various recipient servers. I'm looking into it. In the meantime though, I've noticed that sendmail will NOT ...
0
votes
1answer
156 views

Configuring sendmail to only use starttls in client mode

Is it possible to configure sendmail so that it will only connect to a remote smtp server when STARTTLS is offered there? I so - how do I do it?
0
votes
1answer
304 views

How to generate new CSRs for TLS use in sendmail?

SendMail 8.13.8 | CentOS 5.x Hi Guys, I'm using ca-signed TLS certificates on my sendmail server and they are up for renewal soon. Our new CA doesn't like our old CSR so I need to generate a new ...
1
vote
1answer
1k views

Using trusted certificate key and crt files to enable TLS in Sendmail

I have an SSL certificate and key from a trusted CA (not self-signed). This gives me the following files on a Fedora system: /etc/pki/tls/certs/mydomain.crt /etc/pki/tls/certs/mydomain.csr ...
0
votes
2answers
265 views

SendMail TLS Certificate - Can it be shared for different hosts?

CentOS 5 | SendMail Can TLS certificates be shared between multiple sendmail MTAs? I'm using a CA-signed cert and would prefer to not purchase new certs for each additional sendmail host. -M
2
votes
1answer
1k views

How To Tell SendMail To Explicitly NOT Try TLS For A Domain

CentOS 5.x | Sendmail Hi Guys, I have sendmail setup to perform opportunistic TLS but would like to never use TLS when sending to a specific domain. Is there an entry I can add to /etc/mail/access ...