We have created an EDE testbed at ede.dn5.dk, try to query via <n>.ede.dn5.dk
Please see the IANA Extended DNS Error Codes registry for the full list of defined EDE codes.
$ dig 18.ede.dn5.dk @ede.dn5.dk
; <<>> DiG 9.18.13-1-Debian <<>> 18.ede.dn5.dk @ede.dn5.dk
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 34526
;; flags: qr rd ad; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1
;; WARNING: recursion requested but not available
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1500
; EDE: 18 (Prohibited): (You have requested a prohibited domain!!!)
;; QUESTION SECTION:
;18.ede.dn5.dk. IN A
;; Query time: 21 msec
;; SERVER: 194.165.56.50#53(ede.dn5.dk) (UDP)
;; WHEN: Sun May 21 14:04:28 UTC 2023
;; MSG SIZE rcvd: 89