Score:1

Why does nsupdate fail with "operation canceled"?

cn flag
nh2

I'm trying to dynamically update a DNS server using nsupdate, running nsupdate -k mykey.private -d -v ./my-nsupdate-commands.txt.

But I get the error:

Communication with 192.0.2.0#53 failed: operation canceled

In which cases can nsupdate result in operation canceled?


Full output:

Creating key...
Sending update to 192.0.2.0#53
Outgoing update query:
;; ->>HEADER<<- opcode: UPDATE, status: NOERROR, id:  47216
;; flags:; ZONE: 1, PREREQ: 0, UPDATE: 2, ADDITIONAL: 1
;; ZONE SECTION:
;example.com.        IN  SOA

;; UPDATE SECTION:
mydomain.example.com.    0 ANY A 
mydomain.example.com.    61  IN  A 212.51.139.142

;; TSIG PSEUDOSECTION:
mydomain.example.com.    0 ANY TSIG  hmac-sha512. 1623020003 300 64 ... ... 47216 NOERROR 0 

; Communication with 192.0.2.0#53 failed: operation canceled
Score:1
cn flag
nh2

The target server's firewall may be blocking TCP port 53.

Even though DNS usually uses UDP, nsupdate sometimes needs TCP; see man nsupdate:

By default, nsupdate uses UDP to send update requests to the name server unless they are too large to fit in a UDP request, in which case TCP is used.

cn flag
« `nsupdate` sometimes needs UDP » — did you mean to say TCP here?
cn flag
nh2
@AlexisWilke Yes, thank you, fixed.
mangohost

Post an answer

Most people don’t grasp that asking a lot of questions unlocks learning and improves interpersonal bonding. In Alison’s studies, for example, though people could accurately recall how many questions had been asked in their conversations, they didn’t intuit the link between questions and liking. Across four studies, in which participants were engaged in conversations themselves or read transcripts of others’ conversations, people tended not to realize that question asking would influence—or had influenced—the level of amity between the conversationalists.