isdown

isDown is a web service for system administrators, allowing them to check the availability of their servers

Introduction

isDown gives you the ability to use a third-party for checking if your web service is down or not. Moreover, it allows you to specify a custom expiration timeout, retrieve information in JSON or XML formats, etc.

The isDown ecosystem should not be considered a standalone server on the Internet. Instead, it is an effective federated network. From Wikipedia, a federated network is composed by "multiple computing and/or network providers agreeing upon standards of operation in a collective fashion". In particular, you can install isDown on your own server and connect to other existing and working similar servers.

Preliminary requirements

Following requirements should be satisfied:

• an Apache2 web server
• a publicly reachable IP address for your server

Installation and configuration

1. Access the system as root

2. cd into the /var/www directory of your server

cd /var/www

3. Clone the repository

git clone https://github.com/netsecgroupcnr/isdown.git

4. Set permissions on the isdown folder

chgrp -R www-data isdown

5. Configure the web server to serve the site (on the /var/www/isdown directory)

No further configuration is required. If needed, the $CENTRALNODEURL variable can be manually configured on the settings.php file.

Access

You can access the service through an Internet browser and opening the main website address configured.

Output

Output is available as web page, or in XML and JSON format.

In the XML and JSON cases, it is possible to query the service though a common HTTP request, by adopting the following URL format.

http://$url/?u=$domain&t=$timeout&f=$format

where:

• $url is the domain name of the service on your website
• $domain is the domain to check (also, the format https://www.example.com:8443 is allowed)
• $timeout is the timeout to adopt, in seconds (after the expiration of such timeout, the service will be considered unreachable)
• $format is the format of the generated output (allowed formats are xml and json)

License

The program is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.

Credits

• Idea:
  • Enrico Cambiaso
• Design:
  • Enrico Cambiaso
• Development:
  • Enrico Cambiaso
• Support:
  • Maurizio Aiello
  • Gianluca Papaleo

Contacts

This program is implemented by the NetSec group of CNR-IEIIT.