** Update - Solved **
The issue was solved by editing /etc/postfix/mainf.cf and changing line inet_interfaces = loopback-only as follows:
inet_interfaces = localhost-------------------------------------------------------------------------------------
Hi,
Immediately following my upgrade to arrakis several months ago, email notifications broke. As I use gmail's smtp server and account settings, I verified settings, and attempting a clean reconfigure using a new 2 factor app password, but without success.
Taking a look at /var/log/mail.log reveals:
status=deferred (Host or domain name not found. Name service error for name=smtp.gmail.com type=MX: Host not found, try again)
I have verified (and tried other dns servers) that /etc/resolve.conf is populated correctly:
# Dynamic resolv.conf(5) file for glibc resolver(3) generated by resolvconf(8)
# DO NOT EDIT THIS FILE BY HAND -- YOUR CHANGES WILL BE OVERWRITTEN
nameserver 8.8.8.8
nameserver 8.8.4.4
search google.com
I have also installed dnsutils to do an MX check:
# dig smtp.gmail.com
; <<>> DiG 9.10.3-P4-Debian <<>> smtp.gmail.com
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 57894
;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;smtp.gmail.com. IN A
;; ANSWER SECTION:
smtp.gmail.com. 299 IN CNAME gmail-smtp-msa.l.google.com.
gmail-smtp-msa.l.google.com. 299 IN A 74.125.28.108
gmail-smtp-msa.l.google.com. 299 IN A 74.125.28.109
;; Query time: 47 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Mon Aug 13 17:07:03 PDT 2018
;; MSG SIZE rcvd: 113
If someone could point me in the direction of the solution, I would greatly appreciate it!
Respectfully,