Reliable Server Availability Monitoring

Q: What types of servers can PRTG monitor?

Physical servers, VMware ESXi and Hyper-V VMs, AWS and Azure cloud instances, web servers (Apache, IIS, NGINX), database servers (SQL Server, MySQL, Oracle), application servers, file servers, and mail servers. Windows Server and Linux across the main distributions plus Unix variants. Protocol-wise, SNMP handles cross-platform coverage, WMI goes deeper into Windows-specific metrics, and SSH covers Linux without an agent. Most of that works without installing server monitoring software on the monitored system.

Q: Can PRTG monitor servers in cloud environments like AWS and Azure?

Yes. EC2 instances, RDS databases, and Elastic Load Balancers on AWS. Virtual Machines, SQL Database, and App Services on Azure. Native cloud sensors plus standard protocols depending on what the instance supports. Remote probes can run inside the cloud network or from on-premises. Hybrid setups land in the same view — physical servers, VMware VMs, and cloud instances together. Note: native GCP sensors aren't available out-of-the-box, so Google Cloud coverage needs a different approach.

Q: Does PRTG require agents on servers?

For most environments, no. SNMP, WMI, SSH, and HTTP/HTTPS are already active on the systems you want to monitor. SNMP for Linux and hardware, WMI for Windows and Active Directory, SSH for log checks and custom scripts, HTTP/HTTPS for web servers and APIs. Nothing to install on the monitored server. Remote probes handle distributed environments where you need collectors closer to the monitored segment — they don't sit on individual servers, they collect from a network location.

Catch server outages before users do. Monitor uptime across Windows, Linux, cloud, and on-premises environments

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PRODUCT OVERVIEW

How do you monitor server availability across your entire infrastructure?

Server availability monitoring across mixed environments is rarely a single-tool problem. Windows servers need WMI or SNMP, Linux systems work best with SSH or SNMP, and cloud instances require API-based checks via AWS or Azure credentials. Running separate tools per platform is common, but it means your visibility is fragmented exactly when you need a complete picture most.

Paessler PRTG brings those checks into one platform, running continuous availability monitoring over ICMP ping, SNMP, WMI, and HTTP across physical servers, virtual machines, cloud instances, and on-premises systems. When a server stops responding, notifications go out immediately. Auto-discovery keeps pace with infrastructure changes so new servers, VMs, and cloud instances get picked up without manual updates. Supported environments include Windows Server, Linux (RHEL, Ubuntu, CentOS, Debian), VMware ESXi, Microsoft Hyper-V, AWS EC2, and Azure Virtual Machines.

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PRTG is compatible with all major vendors, products, and systems

Server Monitoring That Keeps Your Infrastructure Running

Stay Ahead of Server Downtime with Continuous Availability Checks

Continuous availability checks mean your team has the information before anyone else does. PRTG runs uptime monitoring using ICMP ping, SNMP uptime sensors, and service status monitoring, and sends notifications immediately via email, SMS, or push when a server stops responding. Your IT teams have enough lead time to start troubleshooting and resolve issues before downtime reaches anyone outside the building.

What PRTG provides:

ICMP ping and TCP port monitoring for instant availability detection across all server types
SNMP uptime sensors that flag failures across operating systems, not just Windows
Customizable thresholds to catch real issues early without drowning in false positives
Notifications routed by severity to the right team via email, SMS, or push
Historical data for spotting outage patterns. Useful for capacity planning, more useful for stopping the same failure from happening twice.

Unified Visibility Across Multi-Vendor Server Environments

Separate server monitoring tools for Windows, Linux, and cloud instances don't just add overhead. They create gaps. When something breaks your team is toggling between dashboards correlating data instead of actually fixing anything.

One platform. SNMP for Linux and network devices, WMI for Windows, SSH when you need agent-free Linux coverage, HTTP/HTTPS for web servers and APIs. All of it lands in a single infrastructure monitoring view showing server availability, performance metrics, and resource utilization across your environment. Also remote probes extend that coverage to branch offices and multi-site setups without opening inbound firewall exceptions, which is worth knowing upfront.

What PRTG provides:

SNMP, WMI, SSH, and HTTP/HTTPS from one platform, no protocol juggling
Physical servers, VMware ESXi and Hyper-V VMs, AWS EC2 and Azure instances in one view
Remote probes for multi-site and branch office environments
Dashboards consolidating server health, CPU usage, disk space, bandwidth, and latency
Auto-discovery keeps pace with infrastructure changes so configuration drift doesn't quietly open monitoring gaps

Prove Server Uptime for SLA Compliance

When an auditor asks for uptime documentation, the answer shouldn't involve spreadsheets and manual log exports. That's a data problem, not a reporting problem.

PRTG retains historical availability data automatically. Outage duration, recovery times, uptime percentages, all of it stored without anyone having to remember to export anything. The PRTG SLA Reporter (an extension you can add separately) turns that into structured compliance reports covering MTBF and MTTR. Ready for audits or stakeholder reviews, no assembly required.

What PRTG provides:

Uptime monitoring with automated historical data collection per monitored server, continuously
SLA Reporter calculates uptime percentages, MTBF, MTTR, and total downtime
Track availability against 99.9%, 99.99%, or 99.999% SLA thresholds
Exportable reports for audits, customer agreements, and capacity planning
Downtime pattern analysis to catch recurring issues before they become the next SLA breach

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PRODUCT OVERVIEW

Keep Monitoring Current as Server Environments Evolve

New servers deploy. VMs spin up. Cloud instances scale out overnight. Manual monitoring configuration doesn't keep pace and the gaps don't show up until an incident reveals what wasn't being watched.

PRTG's auto-discovery scans network ranges continuously. New Windows, Linux, VMware, or cloud-based servers get detected and assigned preconfigured sensors automatically. With 250+ sensor types and device templates, new infrastructure is in server monitoring within minutes. Not a day later after someone remembers to add it.

What PRTG provides:

Auto-discovery scans network ranges and picks up new servers, VMs, and cloud instances as they appear
250+ preconfigured sensors covering Windows, Linux, VMware, AWS, Azure, databases, web servers, network devices
Device templates enforce consistent monitoring configurations across new infrastructure
No coverage gaps when environments scale or migrate
Reduced manual setup for IT teams already stretched across competing priorities

Spot Performance Trends Early and Keep Servers Healthy

Servers give you signals before anything breaks. CPU utilization climbs, disk space fills, memory pressure builds, latency creeps up. PRTG's threshold-based alerts fire when key metrics approach critical levels, giving your team time to act on what the data is already showing. Thresholds are configured per sensor, so alert sensitivity matches the actual requirements of each system. And when upstream failures cascade, dependency mapping keeps the alert queue focused on the actual bottleneck rather than everything downstream from it.

What PRTG provides:

CPU usage, memory, disk I/O, bandwidth, and response time across all server types
Per-sensor warning thresholds, not a global setting that fits no one's environment well
Dependency mapping to reduce noise when upstream failures trigger cascading alerts
Dashboards showing application performance trends over time, not just current state
Historical data for capacity planning, workload optimization, and budget conversations

How PRTG Monitors Server Availability

PRTG's server monitoring uses multiple methods to track server uptime, health, and performance across diverse server environments. Here's how continuous visibility works in practice.

Availability Detection

The starting point is network reachability. PRTG's Ping sensor sends ICMP echo requests to confirm a server responds at the network level. From there the picture gets more specific: SNMP uptime sensors query system status on Linux servers, network devices, and hardware, while TCP port monitoring confirms critical services are actually up and not just the host.

For Windows environments WMI sensors check service states for SQL Server, IIS, or Exchange directly. Linux servers get SSH-based monitoring, no agent required. The HTTP Full Web Page sensor checks whether a web server is returning the right content at an acceptable response time, not just reachable.

Specific sensors:

Ping sensor: ICMP echo requests for network-level availability
SNMP Uptime sensor: Queries system uptime on Linux, network devices, and hardware
WMI Service sensor: Windows service status monitoring (SQL Server, IIS, Exchange)
HTTP Full Web Page sensor: Web server functionality, response time, and content validation

Cross-Platform Monitoring

Different server types need different protocols, and PRTG doesn't force you to pick one. SNMP handles Linux, Unix, network monitoring, and hardware health without vendor dependency. WMI goes into Windows-specific detail: event logs, Active Directory, service dependencies, things SNMP doesn't reach. SSH covers agentless Linux monitoring including custom scripts and log file checks. HTTP/HTTPS handles web server uptime, application response time, and API health.

Protocol use cases:

SNMP: Cross-platform availability, CPU, memory, disk, network bandwidth
WMI: Windows-specific metrics including event logs, Active Directory, service dependencies
SSH: Agentless Linux monitoring, custom application checks, log file monitoring, process tracking
HTTP/HTTPS: Web server uptime, application response time, API health checks

Automated Server Discovery

Auto-discovery in PRTG scans IP ranges, subnets, or Active Directory domains and identifies what's there. Windows servers, Linux systems, VMware ESXi hosts, AWS EC2 instances, Azure VMs, network-attached servers. Once a device is found PRTG applies recommended sensors based on device type. Device templates define the standard sensor set per category so new servers inherit consistent monitoring configurations automatically.

Discovery methods:

IP range scan: Detects devices via ping, identifies type via SNMP or WMI
Active Directory integration: Discovers Windows servers and domain infrastructure
VMware and Hyper-V discovery: Finds virtual machines and host systems
AWS and Azure integration: Discovers cloud instances via API credentials

Threshold-Based Alerts

Thresholds trigger notifications when server metrics cross the levels you define. The more useful piece is dependency mapping.

When an upstream network switch fails and takes 50 servers with it, PRTG sends one alert for the switch rather than 50 server-down notifications. Child sensors pause automatically while the parent is down, so your team sees the actual problem instead of working through a flood of secondary alerts.

Dependency examples:

Network dependencies: Server sensors pause when the upstream switch or router is down
Application dependencies: Web application sensors pause when the database server is unreachable
Master/child relationships: Hierarchical dependency chains from datacenter level down to individual servers

Dashboards and Historical Reporting

Customizable dashboards visualize server availability, performance metrics, resource utilization, and uptime trends using maps, gauges, graphs, and tables. IT teams can create role-specific views. Dashboards refresh every 60 seconds, faster for critical sensors. Historical data tracks uptime percentages, outage frequency, and performance trends for SLA compliance reporting and capacity planning.

Dashboard components:

Top lists: Servers with highest CPU load, lowest disk space, or slowest response time
Status summaries: Servers monitored, overall uptime percentage, sensors currently in alarm
Trend graphs: CPU utilization and disk space consumption over configurable time ranges
Geographic maps: Distributed server locations with real-time status indicators

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Server Availability Monitoring: PRTG vs. Manual Methods

FEATURE	Manual Approach Manual Approach	With PRTG With PRTG
Continuous Availability Monitoring	Manual Approach Check servers individually via ping, login attempts, or wait for user reports	With PRTG Automated availability checks every 60 seconds (or faster) across all servers with instant notifications
Multi-Platform Coverage	Manual Approach Use different server monitoring tools for Windows (Event Viewer, PowerShell), Linux (command-line scripts, Nagios), cloud (AWS CloudWatch, Azure Monitor)	With PRTG Single monitoring solution for Windows, Linux, VMware, AWS, Azure, on-premises, and cloud-based servers using SNMP, WMI, SSH, HTTP
Uptime Tracking & SLA Reporting	Manual Approach Manually log outages, calculate uptime percentages in spreadsheets, export logs from multiple sources	With PRTG Automated historical data collection with PRTG SLA Reporter (extension you can add) generating compliance reports (MTBF, MTTR, uptime %)
Proactive Issue Detection	Manual Approach Wait for crashes, performance complaints, or periodic manual checks to discover server issues	With PRTG Threshold-based alerts notify IT teams when CPU, disk, memory, or latency approach critical levels before failures occur
Centralized Visibility	Manual Approach Log into each server individually, check multiple dashboards, correlate data manually across tools	With PRTG Single dashboard shows server health, uptime, performance metrics, and resource usage across entire infrastructure

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“From a server perspective, we're monitoring all of the key components of our service such as CPU usage, RAM disk space, the Windows services that it's running, and network connectivity of that server. In terms of networks, we’re monitoring all of our switches, firewalls, and access points. It’s really useful to be able to easily pull performance metrics from the PRTG dashboard.”

Ollie Kerslake, Infrastructure Lead

Riverford Organic Farmers

“The tool has given us greater control over all types of devices connected to the network (switches, IP telephony, security cameras, IoT, WiFi) that previously remained opaque when dealing with service incidents. This has improved our ability to diagnose and resolve problems, which has translated into greater efficiency and a better user experience in both internal and public services.”

Jordi Tolosà Bel, New Technologies Technician

Vinaroz City Council

“Our objective was to be able to monitor the health of our most critical servers containing data and applications, but also the flows and bandwidth between headquarters, our 50 servers in the cloud and the 15 servers at our production sites. For us, it is essential to have a proactive approach to understand where the weaknesses of the IT system are to be able to improve them.”

Marc Boullier, CIO

Carambar & Co

Paessler PRTG Network Monitor licenses & pricing

Choose the PRTG Network Monitor subscription that's best for you.

License Name	Price	License Details	Get started	Pricing Details
PRTG 500	^$200	per month paid annually	Buy now Buy now	Enough to monitor multiple aspects of 50 devices
PRTG 1000	^$358	per month paid annually	Buy now Buy now	Enough to monitor multiple aspects of 100 devices
PRTG 2500	^$742	per month paid annually	Buy now Buy now	Enough to monitor multiple aspects of 250 devices
PRTG 5000	^$1,300	per month paid annually	Buy now Buy now	Enough to monitor multiple aspects of 500 devices
PRTG 10000	^$1,642	per month paid annually	Buy now Buy now	Enough to monitor multiple aspects of 1000 devices

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Server Availability Monitoring: Frequently Asked Questions

What is server availability monitoring?

Uptime monitoring tells you whether a server is online, responding, and actually reachable. PRTG's server monitoring runs those checks using ICMP ping, SNMP uptime sensors, WMI system checks, SSH monitoring, and HTTP/HTTPS probes.

People mix this up with performance monitoring but they're not the same thing. Availability is "is it up." Performance is the harder question, CPU usage, disk I/O, memory pressure, latency, response time. A server can be reachable and still be too degraded to matter to the application running on it.

What types of servers can PRTG monitor?

Physical servers, virtual servers (e.g. VMware ESXi and Hyper-V VMs), AWS and Azure cloud instances, web servers (Apache, IIS, NGINX), database servers (SQL Server, MySQL, Oracle), application servers, file servers, mail servers. Windows Server and Linux across the main distributions plus Unix variants.

Protocol-wise SNMP handles cross-platform coverage, WMI goes deeper into Windows-specific metrics, SSH covers Linux without an agent. Most of that works without installing server monitoring software on the monitored system, which matters when you're looking at hundreds of servers.

How does PRTG detect when a server goes down?

ICMP ping checks basic network reachability. TCP port monitoring goes further and confirms whether critical services are actually listening, because a server can respond to ping while the service on it is completely dead. SNMP uptime sensors query device status directly. WMI sensors watch Windows service states.

Notifications go out via email, SMS, push, or different webhookswhen something goes unresponsive. Also worth understanding how dependency mapping fits in here: if a switch fails and takes 50 servers offline PRTG sends one alert for the switch. Working through 50 simultaneous server alerts to find the actual cause is exactly the situation dependency mapping exists to prevent.

Can PRTG monitor servers in cloud environments like AWS and Azure?

Yes. EC2 instances, RDS databases, Elastic Load Balancers on AWS. Virtual Machines, SQL Database, App Services on Azure. Native cloud sensors plus standard protocols depending on what the instance supports.

Remote probes can run inside the cloud network or from on-premises. Hybrid setups land in the same view, physical servers, VMware VMs, cloud instances together. One thing worth flagging upfront: native GCP sensors aren't available out-of-the-box, so Google Cloud coverage needs a different approach.

What's the difference between server availability monitoring and server performance monitoring?

Availability is one question: is the server up and reachable. Ping, uptime checks, service status sensors answer it.

Server Performance is what comes after. CPU, disk space, disk I/O, memory, bandwidth, latency, response time. That's where bottlenecks develop before availability becomes the problem. PRTG does both from the same platform, which means when a performance issue escalates into an outage you're not switching tools mid-incident to figure out what happened.

Does PRTG require agents on servers?

For most environments no. SNMP, WMI, SSH, and HTTP/HTTPS are already active on the systems you want to monitor. SNMP for Linux and hardware, WMI for Windows and Active Directory, SSH for log checks and custom scripts, HTTP/HTTPS for web servers and APIs. Nothing to install on the monitored server.

Remote probes handle distributed environments where you need collectors closer to the monitored segment. They don't sit on individual servers, they collect from a network location. Worth knowing if you're managing a large environment where deploying agents across everything isn't realistic.

Can PRTG monitor both on-premises and cloud servers from one dashboard?

Yes. Deploy probes where the servers are: datacenter, branch office, AWS VPC, Azure virtual network. Everything reports back to one PRTG core server.

Server availability, performance metrics, resource usage across physical, virtual, and cloud in one place. No exporting data between server monitoring tools, no switching dashboards per environment to get a complete picture.