Monitoring probes

Posted Posted by Patrice Guay in Web hosting     Comments 1 comment

Monitoring probes are great tools to help maintain your web presence and avoid downtime for your website. External probes can check at regular intervals the availability and responsiveness of your services while internal ones can monitor resource utilization on your servers. These tools can also provide you with valuable information to help you track down performance issues and diagnose problems on your servers. On this article, we present different monitoring probes:

  • BigBrother
  • munin
  • Nagios
  • OpenNMS
  • pingdom


BigBrother is a solution for IT infrastructure monitoring and diagnostics. It uses a client/server model to provide real-time monitoring for various operating systems (Windows, UNIX, Linux). A BigBrother installation is formed of the following elements:

  • A web server: this server processes the status information and creates a dashboard to display your web solution status. The dashboard can be accessed through any web browser.
  • A notification server: this server processes alerts and dispatches them to the correct people. Notifications can be sent out by e-mail, SMS text, alpha/numeric pages and/or SNMP traps.
  • A network monitor: common network protocols are supported (http/ftp/pop3). Simple text-based protocols can be easily added to the configuration and monitored for availability.
  • Local system monitors: a client must be installed on each monitored server to collect system information and send it to the web and/or notification server.

This commercial software is well-suited for mid-sized to large web solutions.



Munin is a resource monitoring tool that can help analyze resource trends and diagnose performance issues on your servers. It uses a master/node architecture where the master connects to all the nodes at regular interval to collect data. Nodes can be computers, networks, SANs, etc. A piece of software needs to be installed on the nodes to allow communication with the master.

The collected information is stored in RRD files which are transformed into graphs and presented to the end-user through a web interface. Munin uses the OpenSource software RRDTool and its framework is written in Perl, while plugins may be written in any language.The emphasis of munin is on its plug and play capabilities and the ease of creating new plugins (graphs). Munin will help you determine what is different when a performance problem is detected compared to when things were working correctly. It will also help you see how your servers are in term of capacity for various resources (disk capacity, CPU, RAM, network).

This OpenSource software is well-suited for all web solutions.



Nagios is a monitoring system to help you ensure systems, applications, services and business processes are functioning properly. It uses a client/server model to provide real-time monitoring for various operating systems (Windows, Linux, Netware) and network equipment (routers, switches). Therefore, a piece of software needs to be installed on your servers to allow Nagios to collect information about its resources. No software is required on your monitored servers if you only need to monitor publicly available services (HTTP, FTP, SSH, etc.).

In the event of a failure, Nagios can send alerts to allow you to begin remediation processes before outages affect business processes, end-users, or customers. Designed with scalability and flexibility in mind, Nagios will help you reduce the occurrence of unexpected outages.

Nagios is a popular OpenSource software well-suited for mid-sized to large web solutions.



OpenNMS is a network management application platform with four main features:

  • Automated and Directed Discovery
  • Event and Notification Management
  • Service Assurance
  • Performance Measurement

By simply pointing OpenNMS at your network, it will discover services being provided and start monitoring them. Like Nagios, no software is required on your monitored servers if you only need to monitor publicly available services (HTTP, FTP, SSH, etc.). Devices can also be added manually to OpenNMS if you need to have fine-grained control over what is being managed.

OpenNMS can generate its own events or receive events from outside sources, such as SNMP Traps. OpenNMS which is able to handle burst of thousands of events per second, can serve as the central repository for your network event stream. Once important events have been identified, they can generate notices (email, SMS) or trouble tickets through an API allowing bidirectional communication with many trouble ticketing systems (Atlassian JIRA, Best Practical Solutions RT, Concursive ConcourseSuite – formerly Centric CRM, etc.).

The OpenNMS application allow the tracking of Service Level Agreements (SLAs) using synthetic transactions ranging from a simple ICMP request or port check, up through complex website monitoring and round trip e-mail testing. Detailed reports can also be generated on the availability of the services.

To collect performance data, OpenNMS includes support for the SNMP, JMX and HTTP protocols. The HTTP protocol can be used to retrieve data on a web page and use regular expressions to extract values in order to extend an application to integrate with this monitoring tool. Stored data can be converted into graphs and are available through OpenNMS web interface.

This OpenSource software is well-suited for mid-sized to large web solutions.



Pingdom provides an uptime monitoring service. This service monitors the uptime and responsiveness of your web solution from different worldwide locations. It provides information about the availability of your web solution from the Internet perspective. No software is required on your servers to enable this service.

The service provided by Pingdom will discover any problem with your website within minutes. Different monitoring probes can be configured: web checks (HTTP and HTTPS), network checks (ping, specific TCP/UDP port, DNS) and email checks (SMTP, POP3, IMAP). Alerts can be sent through email or SMS. Detailed statistics of your website performance are also available giving you a historical record of all incidents.

This commercial service is well-suited for small to mid-sized web solutions.



Various monitoring software and services are available to help you maintain your web solution availability. Using them will help maintain your web presence and give historical data about the performance of your web solution.

1 Comment to “Monitoring probes”

  • great post, thanks for sharing

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