Wondering how to use monitoring with PRTG? We can help you.

Almost any object with an IP address is possible to monitor using PRTG. It provides us with live readings and periodical usage trends.

We can use them to optimize the layout, efficiency, and setup of leased lines, routers, firewalls servers, and other network components.

As part of our Server Management Services, we assist our customers with several Windows queries.

Today, let us see how to use monitoring with PRTG.

 

What is PRTG?

Hand in hand with various network parameters, PRTG monitors network availability and bandwidth usage. This data is stored in an internal database for later analysis.

To monitor the network, PRTG offers two options:

• PRTG on premises

With PRTG on premises, the PRTG core server and local probe run within our network.

• PRTG hosted by Paessler

It is the PRTG cloud solution, where the PRTG core server and host probe run at Paessler’s end.

 

Use Monitoring with PRTG

In this article, let us see how our Support Techs prepare IT infrastructure for monitoring with PRTG.

• Where to Install PRTG

Our Support Techs always recommend that we install PRTG on premises on a physical machine. We can install it if we have a PC or server with at least a dual-core CPU and 2048 MB RAM.

For remote sites and to distribute the load, we can use remote probes. They collect data and send it over to the core server via a secure connection.

PRTG hosted by Paessler does not require any hardware for the PRTG core server, but at least one remote probe installation is necessary to monitor the local network.

 

• How to Monitor with PRTG

PRTG uses the following ways to receive monitoring data from target devices:

a) Poll or query sensor data:

PRTG can consume and collect sensor data based on interfaces with, for example, HTTP or HTTPS requests, port checks, email checks, File Transfer Protocol (FTP) downloads, and database requests.

b) Listen for or receive sensor data:

PRTG passively receives data that is pushed to PRTG by a device or application. This includes, for example, unexpected events, Syslogs and Simple Network Management Protocol (SNMP) traps, detailed data flow (bandwidth monitoring), and event log messages.

 

• How to Prepare Monitoring

Our Support Techs suggest the first step in comprehensive monitoring is to make a plan.

When we plan what we want to monitor, we add the most important devices within our infrastructure first.

We begin with, our Business Critical Tier-1, the core network and other infrastructure that all network devices depend upon.

This usually includes key infrastructure such as core routers, switches, VPN, firewalls, and basic network services such as DHCP, DNS, and (LDAP).

PRTG monitors, tracks, and charts data, as well as generate alarms.

 

• Types of Logins and Credentials

PRTG needs credentials to access devices in the network. We need different credentials with sufficient permission for all the different devices, operating systems, and domains.

In most cases, PRTG uses the following credential types:

1. SNMP credentials
2. Windows credentials (WMI)
3. Linux, Solaris, and macOS credentials (SSH/Web-based Enterprise Management (WBEM))
4. VMware and XenServer credentials
5. Database management system (DBMS) credentials
6. Other credentials (for example, AWS keys, HTTP proxy)

 

• Monitoring with Simple Network Management Protocol

SNMP monitoring is useful if we are responsible for servers and network devices such as hosts, routers, hubs, and switches.

We can use SNMP to monitor the bandwidth usage of routers and switches on a port-by-port basis, as well as device readings such as memory and CPU load. However, the target devices must support SNMP.

Compared to other bandwidth monitoring technologies, the SNMP option creates the least CPU and network load.

PRTG supports three versions of the Simple Network Management Protocol (SNMP) protocol: version 1, version 2c, and version 3.

The SNMP version depends on our environment. Here are some guidelines:

• If our network is publicly accessible, we can use SNMP v3, which has encryption and secure access.
• If our network is isolated or well-protected behind firewalls, the lower security level of SNMP v1 or SNMP v2c might be sufficient.
• SNMP v2c is preferable if we have a lot of devices to monitor.

The most important aspect is to set the same SNMP version in the PRTG settings as in our target device.

 

• Monitoring Windows Systems

We can monitor Windows systems via Windows Management Instrumentation (WMI) and Windows performance counters.

PRTG uses this technology to access data of various Windows configuration parameters and status values. However, sensors using the WMI protocol generally have a high impact on system performance.

In addition to strict WMI sensors, there are sensors that can use performance counters to monitor Windows systems.

To monitor via WMI and performance counters, it is usually sufficient to provide Credentials for Windows Systems in PRTG. However, monitoring via WMI is not always trivial and often causes issues.

It is also possible to use Simple Network Management Protocol (SNMP) for Windows devices.

 

• Monitoring Passively Received Data

For this purpose, we can set up a device in a way that automatically sends the data to PRTG. Specific sensors can receive this data and alert us based on our individual settings.

For example, all Linux/Unix and most network devices support remote devices generating data that has to be configured on each device and sending the messages to a probe system. Usually, only the destination IP and port are required.

 

• Monitoring with Hypertext Transfer Protocol (HTTP)

Monitoring via HTTP is useful if we want to monitor websites or web servers. It enables us to keep an eye on the availability and download times of a website or the performance statistics of a web server.

This approach lets us include almost any type of device or application in our monitoring.

 

• Notifications from PRTG

PRTG can notify us in various ways if it detects that there is something wrong with our network.

For our critical infrastructure, it is best practice to set up two redundant notifications with different delivery methods.

• Email Notifications

The most common notification method is to send emails with the SMTP server built into PRTG. This means that no SMTP server setup or configuration is required, but if we want to deliver emails through our email server, we have to configure it in the SMTP settings.

• SMS Notifications

To deliver SMS notifications, we can select one of the SMS service providers that PRTG includes by default and use it with our credentials for this provider. We can also use an SMS gateway to receive messages even if our internet connection is down.

• Push Notifications

PRTG can send push notifications to our iOS and Android devices when we run the PRTG app on our smartphones.

 

Troubleshooting common issues with monitoring with PRTG

• Issues with PRTG Desktop

In such a case we first check if we have the same issue when we use the PRTG web interface.

We can find the debug logs for PRTG Desktop in the following directories:

Windows: %AllUsers%\AppData\Roaming\Paessler\PRTG Desktop\data
macOS: \Library\Application Support\Paessler\PRTG Desktop\data

When we uninstall PRTG Desktop, this does not completely remove all custom components from the PRTG Desktop data directory.

To solve this issue, our Support Techs suggest the following steps:

1. Open the Windows registry and delete the registry key HKEY_CURRENT_USER\Software\Paessler\PRTG Desktop.
2. Delete the %AllUsers%\AppData\Roaming\Paessler directory and the %AllUsers%\AppData\Local\Paessler directory.

If it is not possible to simultaneously connect more than two PRTG servers to PRTG Desktop, check the license information.

PRTG Desktop only supports the connection of two Trial Editions or Freeware Editions of PRTG at the same time.

There is no limit to connecting multiple licensed PRTG servers.

• HTTP sensor problems

The web servers will not respond if we do not specify a valid host header in the request.

For each device, there is a simple HTTP sensor with the full URL and it may not load. We get a “Read Timeout” error message on the status page.

PRTG uses a ‘Host Header’ with all its HTTP Sensors, otherwise, they would practically almost always fail.

“Read Timeout” means that the connection to the webserver is established, but PRTG does not receive an answer or an answer that is too short.

Always look at the web server logs, to see why the sensors go into “Read Timeout”.

[Need help with monitoring? We’d be happy to assist]

 

Conclusion

In short, we saw how to use monitoring with PRTG. With PRTG. Today, nearly every business relies on a computer and network infrastructure for internet, internal management, telephone, and email. Here comes the role of PRTG to ensure that business data flows seamlessly between employees, offices, and customers.