testmxlookup(1) on Linux
The text 445c6c685336, as Debian 9 (Stretch) shipped it.
Look up mail relays for a domain
Flags it lists
-
--dnssec -
--udpsize
The text 445c6c685336, as Debian 9 (Stretch) shipped it.
Look up mail relays for a domain
--dnssec
--udpsize