dnssek.info DNSSEC Outage: 2018-06-13

Date: June 14, 2018

Overview

This page gives some details on the dnssek.info DNSSEC outage on June 13, 2018. dnssek.info provides what it calls the "DNSSEC EARLY WARNING SYSTEM (DEWS)" for expiring and expired TLD RRSIGs...

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 June 13, 2018:

June 13, 2018 dnssek.info DNSSEC outage

Zonemaster

dnscheck.iis.se

Google Public DNS

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

With Google Public DNS, because of DNSSEC, queries fail:

$ dig +dnssec a www.dnssek.info. @8.8.8.8

; <<>> DiG 9.4.2-P2 <<>> +dnssec a www.dnssek.info. @8.8.8.8
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 8390
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

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

;; Query time: 265 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Wed Jun 13 07:58:53 2018
;; MSG SIZE rcvd: 44


You have to disable DNSSEC to make DNS queries work:

$ dig +cd a www.dnssek.info. @8.8.8.8

; <<>> DiG 9.4.2-P2 <<>> +cd a www.dnssek.info. @8.8.8.8
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 15543
;; flags: qr rd ra cd; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;www.dnssek.info. IN A

;; ANSWER SECTION:
www.dnssek.info. 3599 IN A 192.101.186.107

;; Query time: 41 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Wed Jun 13 07:58:53 2018
;; MSG SIZE rcvd: 49

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: dnssek.info.
[B] dnssek.info. 3600 IN DNSKEY 256 3 8 ;{id = 38286 (zsk), size = 2048b}
dnssek.info. 3600 IN DNSKEY 257 3 8 ;{id = 532 (ksk), size = 2048b}
[B] Error verifying denial of existence for dnssek.info. type A: No keys with the keytag and algorithm from the RRSIG found
;;[S] self sig OK; [B] bogus; [T] trusted

Logfile examples