# host 172.16.6.39 Host 18.104.22.168.in-addr.arpa. not found: 3(NXDOMAIN)
I believe this used to be proxied through the tools project, so potentially caused by T235627?
I sorted this and cleaned up two other cases of hardcoded IPs in the config:
root@paws-proxy-02:~# grep proxy_pass /etc/nginx/sites-enabled/default # proxy_pass https://172.16.6.39; proxy_pass https://tools.wmflabs.org; # proxy_pass http://172.16.5.206:32611; proxy_pass http://tools-paws-worker-1006.tools.eqiad.wmflabs:32611; # proxy_pass http://172.16.5.206:32612; proxy_pass http://tools-paws-worker-1006.tools.eqiad.wmflabs:32612; root@paws-proxy-02:~#
(I believe these instances are largely unpuppetised)