Check HTTP status code for a page on all DNS records

09-04-2017 | Remy van Elst


Table of Contents


This is a small snippet using curl to check the status code of a given URL on all DNS records for a given domain. This site has a few A records in round robin mode, and sometimes the automatic deployment fails. Using this query I can check which server is the culprit and fix it manually.

The normal HEAD request output also shows all the headers the server sends and that is a pain to scroll through. This just shows me the HTTP status code, which is all I want.

dig +short A raymii.org | awk '{print "echo "$1"; curl -s -k -o /dev/null -I -w \"%{http_code}\" https://"$1"/s/blog/Burn_in_testing_for_Hypervisor_and_Storage_servers.html; echo; echo"}' | bash

Example output:

163.172.129.56
200

185.54.115.97
404

213.187.244.250
000

81.4.120.226
200

The first and last server are correct. The middle one with status code 000 is offline and the 404 code is also not up to date.

For IPv6 and AAAA records, we add brackets:

dig +short AAAA raymii.org | awk '{print "echo "$1"; curl -6 -s -k -o /dev/null -I -w \"%{http_code}\" https://["$1"]/s/blog/Burn_in_testing_for_Hypervisor_and_Storage_servers.html; echo; echo"}' | bash

Example output:

2a00:d880:5:783::2
200

2a04:92c7:e:4d1::5436
200

Tags: bash, curl, dns,