--- title: "Server monitoring with an open-source agent" description: "Monitor CPU, memory, disk and network on Linux servers with a one-line agent install. 15s samples, threshold and no-data alerts, offline spool. €0.50–€0.75 per host." url: https://spectate.net/features/server-monitoring last_updated: 2026-10-26 --- # Know when a server runs out of room > Install the open-source Spectate agent with one command and see CPU, memory, disks and network every 15 seconds, with alerts when a metric stays over its threshold or a host goes quiet. - **One-line install.** One command installs, registers and starts the agent. - **Tiny footprint.** About 13 MB of memory and 1 KB of traffic a minute. - **Nothing lost offline.** Unsent batches wait on disk and are replayed in order. ## One command, then it runs on its own Copy the install command from the dashboard and run it on the server. The agent runs as its own unprivileged user and gets its configuration from Spectate, so there's no config file to keep in sync. - Linux on amd64 and arm64, macOS best effort - One install token for a whole fleet - Signature-checked updates ## CPU, memory, disks and network every 15 seconds CPU, memory and swap, load, disk usage per mount point and traffic per interface, sampled every 15 seconds and sent once a minute. - 15-second samples kept for 30 days - Hourly min, max and average for 13 months - Disk space and inodes per mount point ## Alerts on thresholds and on silence Alert when disk usage stays above 90% or memory runs low, for as long as you choose so short spikes don't wake anyone. A host that stops reporting raises a no-data alert. - Must hold for up to 60 minutes before alerting - No-data alert after 5 minutes by default - Routed like every other alert ## Everything in server monitoring - **On-disk spool.** Up to 50 MB or 24 hours of batches kept during an outage. - **No duplicates.** Replayed batches are recognised, so samples never double. - **Clock correction.** Samples are shifted to match when a server's clock drifts. - **Open source.** Written in Go, published on GitHub, checksummed releases. - **Self-monitoring.** The agent reports its own spool size, failures and memory. - **Same price as a monitor.** A host counts as one monitor on your plan. ## Frequently asked questions ### How do I install the Spectate server agent? Create a host in the dashboard and copy the install command. It is one line, curl piped to sh with your install token. The script downloads and verifies the binary, creates a system user, registers the host and starts a systemd service. Linux on amd64 and arm64 is supported; macOS works on a best-effort basis. ### Which server metrics does Spectate collect? CPU usage split into user, system, I/O wait, steal, idle and more; memory and swap; load averages for 1, 5 and 15 minutes; uptime; disk space and inodes per mount point; and bytes, packets, errors and drops per network interface. Samples are taken every 15 seconds. ### How much overhead does the agent add? Very little. The agent is a static binary of about 10 MB that uses about 13 MB of memory. It sends one gzip-compressed batch per minute, about 1 KB for a typical server with two disks and two network interfaces. It runs as an unprivileged user under a hardened systemd unit. ### What happens when the server loses its connection? The agent keeps collecting. Batches that can't be sent go to an on-disk spool of up to 50 MB or 24 hours and are replayed in order once Spectate is reachable again. The server removes duplicates. If no data arrives for 5 minutes, or the time you set, Spectate raises a no-data alert. ### Can I alert on high disk or CPU usage? Yes. Add a metric condition to the host, for example disk usage above 90 or CPU usage above 80, choose a severity and how long the value must stay over the threshold, from immediately up to 1 hour. The alert follows the host's escalation path and includes a chart of the metric. ### Is the Spectate agent open source? Yes. The agent is written in Go and its source is published on GitHub under the Spectate organisation, so you can read exactly what runs on your servers. Releases are checksummed, and updates installed with spectate-agent update are signature-checked. ## Pricing Included on every plan, from €15 a month (€0.50–€0.75 per monitor). 14-day trial, no credit card. See https://spectate.net/pricing. ## Related - [Uptime monitoring](https://spectate.net/features/uptime-monitoring): Uptime monitoring with HTTP(S), keyword, ping, TCP, DNS and mail checks every 30s from Europe, North America, Asia or Oceania. From €0.50 per monitor. - [Alerting](https://spectate.net/features/alerting): Alerts by email, Slack, Teams, Discord, Telegram, Pushover, webhook, SMS and phone call, with escalation paths that branch on severity, working hours, source and labels. - [On-call](https://spectate.net/features/on-call): On-call schedules with rotations, handoffs and overrides. Pages by email, SMS and phone call with press 1 to acknowledge. Unlimited members from €48 a month on Team.