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Quick check on MX using nslookup

Quick check on MX using nslookup. I’m basically doing this for a reference for myself. I had some weirdness with MX in my zone. I noticed the following message in the logs:


Jul 15 19:32:40 comp.com postfix/smtp[8501]: 4DF9F6540BA: host mx1.xxx.com.xx[xxx.xxx.xxx.xxx] said: 450 4.7.1 <user@xxx.com.xx>... recipient denied, because MX 10 'mail.mydomain.com.' [xxx.xxx.xxx.xxx] for <admin@mydomain.com> not answering (in reply to RCPT TO command)

To lookup MX vis nslookup, simply type nslookup, then ‘enter’. At this point you should be in the nslookup shell. Next, set the type (set type=MX) then the domain you’re looking for.

Quick check on MX using nslookup. I’m basically doing this for a reference for myself. I had some weirdness with MX in my zone. I noticed the following message in the logs:


Jul 15 19:32:40 comp.com postfix/smtp[8501]: 4DF9F6540BA: host mx1.xxx.com.xx[xxx.xxx.xxx.xxx] said: 450 4.7.1 <user@xxx.com.xx>... recipient denied, because MX 10 'mail.mydomain.com.' [xxx.xxx.xxx.xxx] for <admin@mydomain.com> not answering (in reply to RCPT TO command)

To lookup MX vis nslookup, simply type nslookup, then ‘enter’. At this point you should be in the nslookup shell. Next, set the type (set type=MX) then the domain you’re looking for.


nslookup
> set type=mx
> mail.mydomain.com
Server: 127.0.0.1
Address: 127.0.0.1#53

Non-authoritative answer:
*** Can't find mail.mydomain.com: No answer

Authoritative answers can be found from:
mydomain.com
origin = ns1.mydomain.com
mail addr = support.mydomaincom
serial = 2006102100
refresh = 10800
retry = 900
expire = 604800
minimum = 86400

I noticed that I had a goofed up MX entry in the zone file and nslookup verified this for me.

Hope this helps!