We've got a linux server running
sendmail that relays email through our primary mail server, but ever since a change of DNS servers last week, it's been timing out connecting to our mail server. Upon further investigation,
/var/log/maillog shows lines like the following, incl. the incorrect IP address for the mail server:
Apr 4 15:37:32 yip sendmail: p34JVgLE020540: to=<email@example.com>, ctladdr=<firstname.lastname@example.org> (0/0), delay=00:05:50, xdelay=00:02:00, mailer=esmtp, pri=258071, relay=mailserver.domain.tld. [xxx.xxx.xxx.xxx], dsn=4.0.0, stat=Deferred: Connection timed out with mailserver.domain.tld.
Now, we had updated the linux server's DNS servers last week along with the migration by editing
host mailserver.domain.tld, or
nslookup mailserver.domain.tld on the linux server all result in the correct IP address being returned. Where could
sendmail be getting/caching the incorrect IP address and how can I resolve that issue?