mx.glue.umd.edu has no MX records.
Question and response
Question
dig mx.glue.umd.edu. MX
Answer
The response has no answer records.
Authority
glue.umd.edu. 18000 SOA egypt.umd.edu. hostmaster.eng.umd.edu. 2025100201 36000 900 604800 18000
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0