.mg TLD DNSSEC Outage: 2017-09-05

Date: September 5, 2017

Overview

This page gives some details on the .mg (Madagascar) TLD DNSSEC outage on September 5, 2017.

Timeline / DNSViz

DNSSEC Debugger

Unlike DNSViz, Verisign's DNSSEC Debugger doesn't archive results, so here's a screenshot of my web browser's output from September 5, 2017:

September 5, 2017 .mg TLD DNSSEC outage

Zonemaster

drill trace

Since DNSSEC contains so much garbage, I put the complete drill trace into its own file, with the relevant portion below (emphasis added):

;; Domain: mg.
[B] MG. 3600 IN DNSKEY 256 3 5 ;{id = 44863 (zsk), size = 1024b}
MG. 3600 IN DNSKEY 257 3 5 ;{id = 64652 (ksk), size = 2048b}
MG. 3600 IN DNSKEY 256 3 5 ;{id = 32758 (zsk), size = 1024b}
[B] Error verifying denial of existence for mg. type A: No keys with the keytag and algorithm from the RRSIG found
;;[S] self sig OK; [B] bogus; [T] trusted

DNS-OARC: with and without DNSSEC

DNSSEC can be disabled in queries via the CD (checking disabled) bit. Let's compare DNS queries with and without DNSSEC.

With DNSSEC, DNS queries fail:

$ dig +dnssec ns mg. @184.105.193.73

; <<>> DiG 9.10.3-P4-Debian <<>> +dnssec ns mg. @184.105.193.73
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 31925
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags: do; udp: 4096
;; QUESTION SECTION:
;mg. IN NS

;; Query time: 1572 msec
;; SERVER: 184.105.193.73#53(184.105.193.73)
;; WHEN: Tue Sep 05 23:19:55 UTC 2017
;; MSG SIZE rcvd: 31

You have to disable DNSSEC to make DNS queries work:

$ dig +cd ns mg. @184.105.193.73

; <<>> DiG 9.10.3-P4-Debian <<>> +cd ns mg. @184.105.193.73
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 53258
;; flags: qr rd ra cd; QUERY: 1, ANSWER: 6, AUTHORITY: 0, ADDITIONAL: 9

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;mg. IN NS

;; ANSWER SECTION:
MG. 124280 IN NS censvrns0001.ird.fr.
MG. 124280 IN NS b.mg.dyntld.net.
MG. 124280 IN NS ns.dts.mg.
MG. 124280 IN NS ns.nic.mg.
MG. 124280 IN NS ns-mg.malagasy.com.
MG. 124280 IN NS a.mg.dyntld.net.

;; ADDITIONAL SECTION:
a.mg.dyntld.net. 124280 IN A 199.19.5.24
b.mg.dyntld.net. 124280 IN A 199.19.6.24
ns.dts.mg. 85671 IN A 196.192.32.2
ns.nic.mg. 85671 IN A 196.192.42.153
ns-mg.malagasy.com. 124280 IN A 87.98.132.231
censvrns0001.ird.fr. 124280 IN A 91.203.32.147
a.mg.dyntld.net. 124280 IN AAAA 2001:500:92::24
b.mg.dyntld.net. 124280 IN AAAA 2001:500:96::24

;; Query time: 487 msec
;; SERVER: 184.105.193.73#53(184.105.193.73)
;; WHEN: Tue Sep 05 23:19:55 UTC 2017
;; MSG SIZE rcvd: 337

Logfile examples