nih.gov DNSSEC Outage: 2021-04-22

Date: April 22, 2021

Overview

This page gives some details on the US National Institutes of Health (nih.gov) DNSSEC outage on April 22, 2021.

Timeline / DNSViz

Since DNSViz has lots its archives multiple times, here are some 3rd party copies:

And here's a screenshot just in case:

April 22, 2021 nih.gov DNSSEC outage, DNSViz screenshot

DNSSEC Debugger

Unlike DNSViz, Verisign's DNSSEC Debugger doesn't archive results, so here's a screenshot of my web browser's output from April 22, 2021:

April 22, 2021 nih.gov DNSSEC outage

You can also see this snapshot thanks to archive.is.

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.

$ dig +dnssec a nih.gov. @8.8.8.8.

; <<>> dig 9.10.8-P1 <<>> +dnssec a nih.gov. @8.8.8.8.
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 13359
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

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

;; Query time: 3308 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Thu Apr 22 17:27:15 UTC 2021
;; MSG SIZE rcvd: 36


You have to disable DNSSEC to make DNS queries work:

$ dig +cd a nih.gov. @8.8.8.8.

; <<>> dig 9.10.8-P1 <<>> +cd a nih.gov. @8.8.8.8.
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 35389
;; flags: qr rd ra cd; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

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

;; ANSWER SECTION:
nih.gov. 3331 IN A 54.235.145.223

;; Query time: 7 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Thu Apr 22 17:27:15 UTC 2021
;; MSG SIZE rcvd: 52

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):

[T] nih.gov. 3600 IN DS 6318 7 2 6dc9d762020fdf991df60a72d2bddacdfe761f58a0e58cec8998450a5a565793
nih.gov. 3600 IN DS 35355 7 2 3d1ff2755fbacc8958c29fea7a71750848cc259ccd4fb392aa1ca372751c9c25
;; Domain: nih.gov.
;; Signature ok but no chain to a trusted key or ds record
[S] nih.gov. 172800 IN DNSKEY 257 3 7 ;{id = 58971 (ksk), size = 2048b}

nih.gov. 172800 IN DNSKEY 256 3 8 ;{id = 22698 (zsk), size = 1024b}
nih.gov. 172800 IN DNSKEY 256 3 7 ;{id = 2264 (zsk), size = 1024b}
nih.gov. 172800 IN DNSKEY 256 3 7 ;{id = 56039 (zsk), size = 1024b}
nih.gov. 172800 IN DNSKEY 256 3 7 ;{id = 35669 (zsk), size = 1024b}
nih.gov. 172800 IN DNSKEY 257 3 8 ;{id = 17224 (ksk), size = 2048b}
nih.gov. 172800 IN DNSKEY 257 3 8 ;{id = 35449 (ksk), size = 2048b}
[S] nih.gov. 7200 IN A 54.235.145.223
;;[S] self sig OK; [B] bogus; [T] trusted

dns.google.com

dns.google.com saw this outage. See the historical view courtesy of archive.is. Here's a screenshot:

dns.google.com view of April 22, 2021 nih.gov DNSSEC outage

A snapshot of the dns.google.com view was saved by archive.is.

Logfile examples