relay1.exchange.blacknight.com has no SRV records.
Question and response
Question
dig relay1.exchange.blacknight.com. SRV
Answer
The response has no answer records.
Authority
blacknight.com. 3600 SOA ns1.blacknight.com. hostmaster.blacknight.com. 1276188654 14400 7200 2419200 3600
Additional
. 0 OPT ; payload 1280, xrcode 0, version 0, flags 0