I have followed the guide and get the nagios => pager duty working.
The web hook part does not. There are some annoyances as well.
First in the pagerduty web gui when I added the Nagios extension I no longer be able to remove it or even edit it.
Secondly, I have no way to know which protocol that pager duty to talk back to nagios server, http? or https, as the config only allows the root url and no documentation stating what it is
Then thirdly, seems the web hook does not work. I route the cgi url to nginx which reverse proxy to the nagios server and I did not see any request coming from pagerduty at all while testing. Admit that because point 2. I assume pagerduty use https which it should as I have to enter the user and password. and port 80 is not open.
I am not sure if I open port 80 it goes but I am very reluctant to open that port and sending user/password from pagerduty to nagios at all.