.mg TLD DNSSEC Outage: 2019-03-10

Date: March 10, 2019

Overview

This page gives some details on the .mg (Madagascar) TLD DNSSEC outage on March 10, 2019. This is at least the 21st DNSSEC outage for Madagascar.

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 March 10, 2019:

March 10, 2019 .mg TLD DNSSEC outage

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 257 3 5 ;{id = 59263 (ksk), size = 2048b}
mg. 3600 IN DNSKEY 256 3 5 ;{id = 4530 (zsk), size = 1024b}
mg. 3600 IN DNSKEY 257 3 5 ;{id = 64652 (ksk), size = 2048b}
mg. 3600 IN DNSKEY 256 3 5 ;{id = 5307 (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

Google DNS: 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 a mg. @8.8.8.8

; <<>> DiG 9.4.2-P2 <<>> +dnssec a mg. @8.8.8.8
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 45690
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags: do; udp: 512
;; QUESTION SECTION:
;mg. IN A

;; Query time: 30 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Sun Mar 10 20:41:39 2019
;; MSG SIZE rcvd: 31

You have to disable DNSSEC to make DNS queries work:

$ dig +cd a mg. @8.8.8.8

; <<>> DiG 9.4.2-P2 <<>> +cd a mg. @8.8.8.8
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 17787
;; flags: qr rd ra cd; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 0

;; QUESTION SECTION:
;mg. IN A

;; AUTHORITY SECTION:
mg. 1799 IN SOA ns.nic.mg. ramboa.nic.mg. 2019031021 600 3600 604800 3600

;; Query time: 31 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Sun Mar 10 20:41:39 2019
;; MSG SIZE rcvd: 70

Logfile examples