Use Asterisk for Nagios Notifications

Solution

This is a description about how to connect Nagios to Asterisk.
So you can receive automatic phone calls if Nagios reports some failure.

There is also another script online that lets your Nagios box call thru the Asterisk Manager protocol (that way you can have your Nagios installation on a separate box).

Components

• Operating system: Red Hat, CentOS, Fedora or Ubuntu
• Monitoring software: Nagios
• VoIP software: Asterisk
• Text-to-speech software: Cepstral TTS

Tested scenario

• Ubuntu 8.04
• Nagios 3.0.1
• Cepstral Swift 4.2.1
• Asterisk 1.4.17

Nagios configuration

Contacts

/usr/local/nagios/etc/objects/contacts.cfg

[...]
define contact{
        contact_name                    nagiosadmin
        use                             generic-contact
        alias                           Nagios Admin
        service_notification_commands   notify-service-by-phone
        host_notification_commands      notify-host-by-phone
        email                           [email protected]
        address2                        SIP/1000
        }
[...]

Notification command

vim /usr/local/nagios/etc/objects/commands.cfg

[...]

define command{
        command_name notify-host-by-phone
        command_line $USER1$/notify-by-phone.sh $CONTACTADDRESS2$ "Nagios Host Alarm. Notification Type: $NOTIFICATIONTYPE$. Host: $HOSTNAME$. State: $HOSTSTATE$. Address: $HOSTADDRESS$ Info: $HOSTOUTPUT$ Time: $LONGDATETIME$" _host_$HOSTEVENTID$
        }

 

define command{
        command_name notify-service-by-phone
        command_line $USER1$/notify-by-phone.sh $CONTACTADDRESS2$ "Nagios Service Alarm. Notification Type: $NOTIFICATIONTYPE$. Service: $SERVICEDESC$. Host: $HOSTALIAS$. Address: $HOSTADDRESS$. State: $SERVICESTATE$. Time: $LONGDATETIME$. Additional Info: $SERVICEOUTPUT$" _service_$SERVICEEVENTID$
}

[...]

Asterisk configuration

/etc/asterisk/extensions.conf

[...]

[alarm]
exten => s,1,Answer
exten => s,2,NoOp(alarmid: ${alarmid})
exten => s,3,Playback(/var/spool/alarm/alarm${alarmid})
exten => s,4,Hangup
[...]

Connection script

see also Asterisk auto-dial out
/usr/local/nagios/libexec/notify-by-phone.sh

#!/bin/bash
channel=$1
alarmtext=$2
alarmid=$3

cd /var/spool/alarm
echo $alarmtext > alarm$alarmid.txt
/opt/swift/bin/swift -n Allison-8KHz -f alarm$alarmid.txt -o alarm$alarmid.tmp.wav
/usr/bin/sox alarm$alarmid.tmp.wav -r 8000 alarm$alarmid.ul
/bin/mv -f alarm$alarmid.ul alarm$alarmid.ulaw
/bin/rm alarm$alarmid.tmp.wav
 
echo "Channel: $1
MaxRetries: 2
RetryTime: 60
WaitTime: 30
Context: alarm
Extension: s 
Priority: 1
Set: alarmid=$alarmid" > alarm$alarmid.call 

/bin/chmod 777 alarm$alarmid.call 
/bin/mv alarm$alarmid.call /var/spool/asterisk/outgoing

Setup procedure

prerequisites: Nagios, Asterisk and Cepstral installed

as root:

apt-get install sox
apt-get install libsox-fmt-all
mkdir /var/spool/alarm
chown nagios.asterisk /var/spool/alarm/

usermod -G nagcmd,asterisk nagios
vim /usr/local/nagios/libexec/notify-by-phone.sh   # (copy and paste above script)
chown nagios.nagios /usr/local/nagios/libexec/notify-by-phone.sh 
chmod 750 /usr/local/nagios/libexec/notify-by-phone.sh
vim /usr/local/nagios/etc/objects/contacts.cfg  # (copy and paste above config)
vim /usr/local/nagios/etc/objects/commands.cfg  # (copy and paste above config)
/etc/init.d/nagios reload
vim /etc/asterisk/extensions.conf   # (copy and paste above config)
/etc/init.d/asterisk reload

Test via command line

su nagios
/usr/local/nagios/libexec/notify-by-phone.sh SIP/1000 "hello world" first_test_id