Your Server Hit 98% CPU at 2 AM. Nobody Noticed Until Morning.
Visual Sentinel monitors server health alongside your websites. One dashboard for infrastructure and application monitoring.
free plan · optional no-card trial · 60-second setup
What Is Server Monitoring?
Server monitoring is the practice of continuously tracking the health, performance, and availability of your servers in real time. A server monitoring tool collects metrics like CPU usage, memory consumption, disk space, network throughput, and running processes, then alerts you the moment something crosses a threshold you define. Without server monitoring, problems like memory leaks, disk filling up, or runaway processes go unnoticed until they cause downtime. By the time a user reports a slow page or a checkout failure, the root cause is often a server that has been struggling for hours. Server health monitoring closes that gap by giving you visibility into what is happening inside your infrastructure, not just whether a URL responds. Visual Sentinel takes this further by combining server monitoring tools with website monitoring in a single platform. Instead of running one tool for infrastructure metrics and another for uptime, SSL, performance, DNS, and visual regression, you get a unified dashboard where server fleet health and website status live side by side. Our lightweight agent installs in one command, reports metrics every 60 seconds via HTTPS, and tracks CPU (user, system, idle breakdowns), memory (including cache and swap), disk (usage and I/O throughput), network (bytes and packets in both directions), load averages, uptime, and the top processes consuming resources. You set custom thresholds for CPU, memory, and disk, and when any metric breaches your limit, alerts fire instantly through email, Slack, Discord, Telegram, WhatsApp, or custom webhooks. Historical data is retained for 7 days with interactive charts so you can spot trends, correlate server spikes with application issues, and plan capacity before you run out of headroom.
Built for issues
customers actually notice.
CPU, Memory, Disk & Network
Track all four pillars of server health in real time. CPU breakdowns (user/system/idle), memory with swap, disk I/O, and network throughput, updated every 60 seconds.
Threshold-Based Alerts
Set custom thresholds for CPU, memory, and disk usage. When any metric breaches your limit, get alerted via email, Slack, Discord, Telegram, WhatsApp, or webhooks.
One-Command Agent Install
Install the monitoring agent with a single curl command. No package managers, no dependencies beyond curl and jq. Works on Linux, macOS, Windows, and FreeBSD.
Process Monitoring
See the top 10 processes by CPU usage on each server. Identify runaway processes, memory hogs, and zombie tasks before they take your server down.
Server + Website in One Dashboard
No need for separate infrastructure and application monitoring tools. Server metrics, uptime, SSL, DNS, performance, and visual checks, all in one place.
7-Day Historical Charts
Interactive charts for every metric over the past 7 days. Spot trends, correlate spikes with deployments, and plan capacity before you run out of headroom.
Apache, Tomcat, IIS, and SQL Server monitoring
Generic CPU and memory metrics tell you the host is busy. Stack-specific monitoring tells you which service is busy and why. Visual Sentinel combines host-level metrics with website-layer checks against the public endpoints those services serve.
Apache web server monitoring
Apache HTTP Server runs roughly a third of the active web. The common Apache failure modes are MaxRequestWorkers exhaustion, slow PHP-FPM backends choking the worker pool, and module misconfigurations that return 500s under load. Visual Sentinel pairs the host-level agent (CPU, memory, load average) with website monitoring against the URLs Apache serves. When the worker pool fills, you see the host CPU climb at the same time uptime checks start timing out, and the incident detail surfaces both signals together.
For deeper Apache-specific metrics (busy workers, requests per second, scoreboard state), enable mod_status with a localhost-restricted handler and point a Visual Sentinel content monitor at the status page. The content layer extracts the busy-worker count on every check; cross-region uptime checks confirm the URLs the workers serve are healthy. No Apache-specific agent module required.
Apache Tomcat monitoring
Tomcat sits between the JVM and the application. The common Tomcat failure modes are heap exhaustion (full GC stalls), thread-pool saturation under burst load, and slow JDBC pool exhaustion when a downstream database stalls. Host-level metrics catch the symptoms (high CPU during full GC, memory pressure on heap-bound workloads); the website-layer checks confirm whether requests still get through.
For Tomcat-specific signals, expose JMX over a localhost MBean server and bind a /metrics endpoint via Spring Boot Actuator or Micrometer. Visual Sentinel content monitors can scrape that endpoint for Tomcat thread-pool depth, JVM heap, and GC pause percentage on the same schedule as your host metrics. Combine with uptime monitoring on the public-facing URLs and you get a Tomcat health view that is both app-aware and visitor-aware.
IIS (Windows) monitoring
Microsoft Internet Information Services runs on Windows Server and is the dominant web server for ASP.NET workloads. The common IIS failure modes are application pool recycles spiking memory, request-queue saturation under bursts, and 503 Service Unavailable errors when the worker process restarts. The Visual Sentinel agent supports Windows directly (PowerShell-based metric collection), so CPU, memory, disk, and network are all tracked alongside Linux servers in the same dashboard.
Pair the host-level metrics with uptime and visual checks against the URLs IIS serves. When the worker process recycles, you see the gap in successful uptime checks correlate with the CPU and memory drop on the host; the alert surfaces both. For deeper IIS metrics (current connections, requests per second per app pool), expose a /metrics endpoint via the IIS Administration API or a custom HttpModule and point a content monitor at it.
SQL Server monitoring
Microsoft SQL Server failures usually start with one of: tempdb pressure, lock-escalation deadlocks, plan-cache bloat, or AlwaysOn Availability Group sync lag. The host-level Visual Sentinel agent tracks CPU, memory pressure, disk I/O, and disk-queue depth on the database server, all of which surface SQL-bound workload issues before queries start timing out at the application layer.
For SQL Server-specific signals (active connections, blocked sessions, wait stats, replica lag), expose an authenticated /metrics endpoint that runs the relevant DMV queries and returns the result. Visual Sentinel content monitors scrape this on the same cadence as host metrics, so a single incident timeline shows you the host pressure, the application-layer outage, and the underlying SQL Server signal that triggered it. Uptime monitoring on the public URLs that depend on the database closes the loop: when the database stalls, the website monitor catches the user-facing impact.
Three steps,
no extensions.
Add Your Server
Enter your server name, hostname, and operating system. Visual Sentinel generates a unique agent token for secure communication.
Run the Install Script
Copy the one-line curl command and run it on your server with sudo. The agent installs in seconds and begins reporting metrics every minute via cron.
Set Thresholds & Get Alerts
Configure CPU, memory, and disk alert thresholds. Choose your notification channels. Visual Sentinel alerts you the moment a metric breaches your limits.