.mg TLD DNSSEC Outage: 2018-12-30

Date: December 30, 2018

Overview

This page gives some details on the .mg (Madagascar) TLD DNSSEC outage on December 30, 2018.

Timeline / DNSViz

2018-12-30 19:54:19 UTC — Signature inception is 32 minutes in the future
2018-12-30 19:54:50 UTC — Signature inception is 32 minutes in the future
2018-12-30 19:55:03 UTC — Signature inception is 32 minutes in the future
2018-12-30 19:55:42 UTC — Signature inception is 31 minutes in the future
2018-12-30 20:24:10 UTC — last personally observed DNSSEC failure
2018-12-30 20:27:04 UTC — RRSIGs become valid

DNSSEC Debugger

Unlike DNSViz, Verisign's DNSSEC Debugger doesn't archive results, so here's a screenshot of my web browser's output from December 30, 2018:

Zonemaster

Note: zonemaster requires javascript.

zonemaster.net archived "The apex DNSKEY RRset was not correctly signed."
zonemaster.fr archived "The apex DNSKEY RRset was not correctly signed."

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 = 5307 (zsk), size = 1024b}
mg. 3600 IN DNSKEY 257 3 5 ;{id = 64652 (ksk), size = 2048b}
mg. 3600 IN DNSKEY 257 3 5 ;{id = 59263 (ksk), size = 2048b}
[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 ns mg. @8.8.8.8

; <<>> DiG 9.4.2-P2 <<>> +dnssec ns mg. @8.8.8.8
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 34240
;; 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 NS

;; Query time: 397 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Sun Dec 30 19:55:30 2018
;; MSG SIZE rcvd: 31

You have to disable DNSSEC to make DNS queries work:

$ dig +cd ns mg. @8.8.8.8

; <<>> DiG 9.4.2-P2 <<>> +cd ns mg. @8.8.8.8
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 28158
;; flags: qr rd ra cd; QUERY: 1, ANSWER: 5, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;mg. IN NS

;; ANSWER SECTION:
mg. 7199 IN NS ns-mg.malagasy.com.
mg. 7199 IN NS ns.dts.mg.
mg. 7199 IN NS ns.nic.mg.
mg. 7199 IN NS censvrns0001.ird.fr.
mg. 7199 IN NS pch.nic.mg.

;; Query time: 31 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Sun Dec 30 19:55:30 2018
;; MSG SIZE rcvd: 145

Logfile examples

[1546199726] unbound[27504:0] info: validation failure <mg. NS IN>: signature before inception date from 91.203.32.147 for key mg. while building chain of trust
[1546201450] unbound[27504:0] info: validation failure <mg. NS IN>: signature before inception date from 204.61.216.121 for key mg. while building chain of trust