Dec 9 13:38:01 mybox sendmail: mB00Z00k000000: to=<firstname.lastname@example.org>, delay=00:03:00, xdelay=00:03:00, mailer=esmtp, pri=000000, relay=sub.domain.ext. [00.000.000.00], dsn=4.0.0, stat=Deferred: Connection timed out with sub.domain.ext.
I've change domains & numbers to zeros for security.
What gives with the error? There are a number of them going back several days. sub.domain.ext pings successfully.