check_dshield_infocon.pl is a nagios plugin for checking the DSheild Infocon 
level.

i. Dependencies
Perl
Nagios' utils.pm
REST::Client

ii. Installation
1. copy check_dshield_infocon.pl to your nagios plugin directory and edit the 
"use lib" line to point to where the utils.pm file resides. 
2. Add a command to your nagios config to run the command. Below is a sample:

define command{
    command_name    check_dshield_infocon
    command_line    $USER1$/contrib/check_dshield_infocon.pl
}

3. Add isc.sans.edu as a host to check. Perhaps use check_http as a host 
check. That way if the website is down, you error messages will be clearer.

define host{
    host_name               dsheild
    alias                   ISC DShield
    address                 isc.sans.edu
    check_command           check_http
    max_check_attempts      3
    check_period            24x7
    contacts                security_team
    notification_interval   120
    notification_period     24x7
}

4. Define a service to use the command to check that level

define service{
    host_name               dsheild
    service_description     ISC DSheild Status
    check_command           check_dsheild_infocon
    max_check_attempts      1
    check_interval          60
    retry_interval          60
    check_period            24x7
    notifiction_interfaval  24x7
    contacts                security_team
}