If you don't already have a PagerDuty "Nagios" service, you should create one:

• In your account, under the Services tab, click "Add New Service".
• Enter a name for the service and select an escalation policy. Then, select "Nagios" for the Service Type.
• Click the "Add Service" button.
• Once the service is created, you'll be taken to the service page. On this page, you'll see the "Service key", which will be needed when you configure your Nagios server to send events to PagerDuty.

Install the necessary Perl dependencies:

aptitude install libwww-perl libcrypt-ssleay-perl

Copy over pagerduty_nagios.cfg:

wget https://raw.github.com/PagerDuty/pagerduty-nagios-pl/master/pagerduty_nagios.cfg

Open the file in your favorite editor. Enter the service key corresponding to your Nagios service into the pager field. The service key is a 32 character string that can be found on the service's detail page.

Copy the Nagios configuration file into place:

cp pagerduty_nagios.cfg /etc/nagios3/conf.d

Add the contact "pagerduty" to your Nagios configuration's main contact group. If you're using the default configuration, open /etc/nagios3/conf.d/contacts_nagios2.cfg and look for the "admins" contact group. Then, simply add the "pagerduty" contact.

define contactgroup{ 
  contactgroup_name       admins
  alias                   Nagios Administrators
  members                 root,pagerduty   ; <-- Add 'pagerduty' here.
}

Download pagerduty_nagios.pl:

wget https://raw.github.com/PagerDuty/pagerduty-nagios-pl/master/pagerduty_nagios.pl
cp pagerduty_nagios.pl /usr/local/bin

Make sure the file is executable by Nagios:

chmod 755 /usr/local/bin/pagerduty_nagios.pl

Enable environment variable macros in /etc/nagios3/nagios.cfg (if not enabled already):

enable_environment_macros=1

Edit the nagios user's crontab:

crontab -u nagios -e

Add the following line to the crontab:

* * * * * /usr/local/bin/pagerduty_nagios.pl flush

Restart Nagios:

/etc/init.d/nagios3 restart

Install the necessary Perl dependencies:

yum install perl-libwww-perl perl-Crypt-SSLeay

Download pagerduty_nagios.cfg:

wget https://raw.github.com/PagerDuty/pagerduty-nagios-pl/master/pagerduty_nagios.cfg

Open the file in your favorite editor. Enter the service key corresponding to your Nagios service into the pager field. The service key is a 32 character string that can be found on the service's detail page.

Copy the Nagios configuration file into place:

cp pagerduty_nagios.cfg /etc/nagios

Edit the Nagios config to load the PagerDuty config. To do this, open /etc/nagios/nagios.cfg and add this line to the file:

cfg_file=/etc/nagios/pagerduty_nagios.cfg

Add the contact "pagerduty" to your Nagios configuration's main contact group. If you're using the default configuration, open /etc/nagios/localhost.cfg and look for the "admins" contact group. Then, simply add the "pagerduty" contact.

define contactgroup{ 
  contactgroup_name       admins
  alias                   Nagios Administrators
  members                 root,pagerduty   ; <-- Add 'pagerduty' here.
}

Download pagerduty_nagios.pl and copy it to /usr/local/bin:

wget https://raw.github.com/PagerDuty/pagerduty-nagios-pl/master/pagerduty_nagios.pl
cp pagerduty_nagios.pl /usr/local/bin

Make sure the file is executable by Nagios:

chmod 755 /usr/local/bin/pagerduty_nagios.pl

Enable environment variable macros in /etc/nagios/nagios.cfg (if not enabled already):

enable_environment_macros=1

Edit the nagios user's crontab:

crontab -u nagios -e

Add the following line to the crontab:

* * * * * /usr/local/bin/pagerduty_nagios.pl flush

Restart Nagios:

/etc/init.d/nagios3 restart

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