I've got an outbound mail server that handles all the internal email generated by our various app servers and I need to get DKIM signing working so we can get hotmail to actually accept our mail.
I followed a couple of online guides and have postfix talking to dkim-milter, but it still refuses to sign the email.
Jul 20 15:39:21 mail2 dkim-filter: BB9742E70149: no signature data
I had an issue with dkim-milter thinking my servers were external, but I added the -I option in /etc/sysconfig/dkim-milter pointing to a local file containing all the hostnames of my app servers, so that error stopped, but now I'm stuck.
I am not accepting any incoming mail on this server, it is purely mail out and I do a replace on the message-id and reply-to addresses to scrub any references to internal hosts. Not sure if that makes a difference in the processing.