to=<firstname.lastname@example.org>, relay=none, delay=21311, delays=21301/0.04/10/0, dsn=4.4.3, status=deferred (Host or domain name not found. Name service error for name=localdomain type=MX: Host not found
When I run the following command on my postfix client, it does resolve. mail.p.example.com hosts our postfix server, which then relays emails to gmail smtp.
host -t MX p.example.com p.example.com mail is handled by 10 host.p.example.com.
I compare my postfix config with a working config on another host and they're the same.
inet_protocols = ipv4 mynetworks_style = host inet_interfaces = loopback-only relayhost = $mydomain
There's more to the config than what I pasted above but nothing related to dns. smtp_host_lookup hasn't been set (default value = dns).
I do not have any resolv.conf files under /var/spool/postfix. Would appreciate any directions on how postfix resolves DNS records.