DNS port Randomness Test

https://www.dns-oarc.net/oarc/services/dnsentropy

Also check this out:

red@cricket-lnx:~$ dig +short porttest.dns-oarc.net TXT @red-cricket
porttest.y.x.w.v.u.t.s.r.q.p.o.n.m.l.k.j.i.h.g.f.e.d.c.b.a.pt.dns-oarc.net.
"xxx.69.2.xxx is GREAT: 26 queries in 0.2 seconds from 26 ports with std dev 20345"