Lazy DNS

I had a call this morning from a customer who wanted me to come down because their mail server was broken. They had experienced an ISP outage, which subsequently was fixed, but their mail server wasn't getting anything still.

I was actually ready to go out the door when I thought to just double check reality, and that check kept me sitting right here:

$ dig +short xyz.com mx
10 mail.xyz.com.xyz.com.
20 mail2.xyz.com.xyz.com.

Ooops.. that certainly can't be right. I told the client that his MX records were munged, but he came back with a screen from the DNS providers tools that seemed to show them correctly. It looked something like this:

I told him to try taking out the ".xyz.com", but he said the tool told him that was invalid.. at which point I smiled to myself and knew what he had to do.

Do you know what he needed to do to fix this?

Answer

Finnish Translation by Thor Kottelin available at /Detective/lazy_dns.fi.html
Swedish Translation by Thor Kottelin available at /Detective/lazy_dns.sv.html

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