3R Monitor
Free, self-hosted monitoring for your servers and websites. Live server metrics, website and SSL checks, outage emails, vulnerability alerts and traffic control — one program on your own Linux server.
Version 1.1.1 · 28 Oct 2026 · How to install
Your servers and websites, live, in one panel.
One Go program on your own Linux server. Agents on each server push their metrics every 3 seconds over outbound HTTPS only: the monitored servers open no inbound port. Free of charge, closed source, by 3R SOFT; in English, Spanish and Chinese.
Live server metrics
CPU, memory, disk and services of every server, refreshed every 3 seconds.
Website and API checks
Availability of your websites and APIs, SSL certificates and DNS, checked around the clock.
Outage emails
An email as soon as a server, a service or a website goes down.
Vulnerability matching
Every day, the software installed on your servers is matched against OSV, CVE and the CISA KEV catalog.
Traffic and firewall
Traffic by country and IP, with allowlists and blocklists that the agent enforces in the server’s firewall.
World map and wall display
Every server on a live world map, and a wall-display mode for the operations screen.
Install it on your Linux server.
Download the package to the server, then unpack it and run the installer:
tar xzf 3rmonitor-1.1.1.tar.gz && cd 3rmonitor-1.1.1 && sudo bash install.shRuns on Linux. Free of charge; new versions appear in the panel and install with one click.