temple.edu DNSSEC Outage: 2018-09-23

Date: September 23, 2018

Overview

This page gives some details on the temple.edu (Temple University) DNSSEC outage on September 23, 2018. Temple has around 40,000 students.

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 23, 2018.

September 23, 2018 temple.edu DNSSEC outage

Google Public 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 result in SERVFAIL:

$ dig +dnssec ns temple.edu. @8.8.8.8

; <<>> DiG 9.4.2-P2 <<>> +dnssec ns temple.edu. @8.8.8.8
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 7318
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags: do; udp: 512
;; QUESTION SECTION:
;temple.edu. IN NS

;; Query time: 147 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Sun Sep 23 05:35:09 2018
;; MSG SIZE rcvd: 39

$ dig +cd ns temple.edu. @8.8.8.8

; <<>> DiG 9.4.2-P2 <<>> +cd ns temple.edu. @8.8.8.8
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 60924
;; flags: qr rd ra cd; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;temple.edu. IN NS

;; ANSWER SECTION:
temple.edu. 3599 IN NS ns1.temple.edu.
temple.edu. 3599 IN NS ns2.temple.edu.

;; Query time: 78 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Sun Sep 23 05:35:09 2018
;; MSG SIZE rcvd: 64

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: temple.edu.
;; Signature ok but no chain to a trusted key or ds record
[S] temple.edu. 3600 IN DNSKEY 256 3 7 ;{id = 46170 (zsk), size = 1024b}
temple.edu. 3600 IN DNSKEY 257 3 7 ;{id = 37155 (ksk), size = 2048b}
temple.edu. 3600 IN DNSKEY 256 3 7 ;{id = 32274 (zsk), size = 1024b}
[S] temple.edu. 86400 IN A 155.247.166.60
;;[S] self sig OK; [B] bogus; [T] trusted

Logfile examples