Paessler PRTG Network Monitor 25.4 review: The network monitoring host with the most

Businesses that want to monitor absolutely everything on their network will find Paessler's PRTG Network Monitor an appealing choice. Many competing products employ device-based licensing and use a modular approach, which can leave you with a mounting bill for optional extras. But PRTG takes a much simpler approach as it's licensed only by the number of active sensors.

A sensor allows a single resource to be monitored, which could be anything from a CPU core, a network interface, or service to one port on a network switch or firewall. Sensor licences can be very cost-effective when you want to control precisely what individual resources are to be monitored.

This approach means there are no hidden costs, as a subscription enables access to all sensors. PRTG comes into its own if you want to monitor virtualization hosts, applications, and even NetFlow feeds, as some vendors only offer these features as chargeable add-on modules.

Paessler operates a rolling update process so as new sensors and features become available, they're yours for the taking. PRTG has a sensor for every occasion with the latest v25.4 on review, offering 321. However, more importantly, it introduces a new user interface, which is currently in alpha testing.

Paessler PRTG Network Monitor 25.4 review: Deployment and discovery

We've been running PRTG in the lab for over eight years and recently migrated it to a repurposed HPE 1U rack server running Windows Server 2022. Hardware demands are modest as the eight CPU cores and 16GB of DDR4 in our host system can handle up to 5,000 sensors, which is sufficient for monitoring around 500 devices.

Those new to PRTG can choose to install it on-premises or save on hardware costs with Paessler's cloud-hosted version. Paessler offers a 30-day unrestricted trial, or you can try it out for as long as you like with a free version that enables 100 sensors.

Either way, you'll find deployment a breeze as a network discovery wizard identifies all devices and assigns a base set of sensors to them, along with pre-set threshold triggers for automatic alerting. Paessler offers an extensive range of monitoring choices as you can access the PRTG core server via its web console, use the Windows or Mac desktop apps, and choose from free iOS and Android mobile apps.

The web console home page presents two donut charts providing insights into used sensors and alarms and even a quick glance reveals how quickly they can get used up. Our lab setup includes a firewall, a 52-port switch, one VMware and three Hyper-V virtualisation hosts, six physical Windows Server systems, two NAS appliances, and a network printer, which combined to slurp up over 700 sensors.

The good news is you can review the components you want to monitor, delete the sensors you don't need, and return them to the pool for use elsewhere. This makes PRTG a lot more flexible than products that employ device-based licensing.

Paessler PRTG Network Monitor 25.4 review: Monitoring and alerting

All monitored items are viewed from the Devices page, and the main tree view automatically organises all systems into hierarchical groupings where they inherit settings such as discovery schedules and login credentials from their parent group. This can get very busy for larger networks, but the view can be customised for your environment by creating new groups and moving monitored systems over to them.

It's easy to identify problems as all sensors are assigned colour-coded icons showing if they are up, down, paused, or in a warning state while sensor pop-up windows provide live graphs and alert messages. Selecting a device or sensor takes you to a detailed overview with live graphs and charts showing activity for the past two days, month, and year.

You can add extra sensors to a device by selecting it and choosing the Recommended Sensors option below its metrics table, or add them manually by using the search facility in the main Sensors page. We had no problems adding PRTG's Redfish sensors to our iDRAC and iLO devices, which gathered detailed information on server health, power supplies, and storage.

PRTG uses sensor state and threshold triggers to perform actions such as executing a program and sending out alert notifications using a wide variety of methods, including email, SNMP trap, SMS, or Syslog, and linking up with other services, including Microsoft Teams, ServiceNow, and Slack. You can set values for sensors at any level of the group hierarchy, and options include state or speed changes, threshold breaches, and traffic volume levels.

Paessler PRTG Network Monitor 25.4 review: New user interface

You can enable the new UI from the console's setup page, and it's clear this isn't just an update, but a complete redesign. As it's in early alpha testing, the home page opens with a bunch of cards highlighting the new features and offering quick links to try them out.

All menus have been moved to the left side for easier access and selecting the Monitoring option presents a new window in the main pane that bears many similarities to PRTG's desktop app. It presents the same split screen view so you can browse through monitored items in the left pane, select a device or sensor, and view all its metrics in the pane to the right.

The main view sees substantial changes as it provides a list of all status icons across the top so you can filter the view to show specific types, such as only those that are down. If you've selected a device, a ribbon menu below these has options for displaying an overview, the associated sensors, logs, settings, and triggers.

Selecting a sensor changes the ribbon menu to show an overview, but with options to view channels and a set of linear performance graphs. The web UI has also been updated so it auto-scales its size when loaded on a mobile device, but if you prefer the older UI, you can swap back to it with one mouse click.

Paessler PRTG Network Monitor 25.4 review: Is it worth it?

Paessler offers a range of affordable subscriptions, with the starter PRTG 500 pack costing €137 per month, paid yearly, which should be sufficient to monitor up to 50 devices. You can easily upgrade to larger sensor packs when required, and the cloud-hosted version also looks good value with a Hosted 500 subscription only costing a little more than the on-premises option.

You will need to tame its sensor usage, but Paessler's PRTG is a highly versatile network monitoring solution capable of providing a wealth of information about devices, applications, and services. All sensors are included in your subscription, so you don't need to worry about optional modules, and the new web interface promises to make it even easier to use.