OS Agent - Monitor

The Monitor tab lists every host that pushes metrics to this Collector, with their status and last activity. It is also where you can link a host to a System, deactivate it, or remove it.

Each row shows:

Click a row to expand the detail for the host.

• OK (green) - the host is active and has pushed within the last 5 minutes
• ERROR (red) - the host is active but has not pushed in the last 5 minutes
• OFF (grey) - the host is set inactive in the Collector - all incoming pushes for this host are rejected

The 5-minute threshold is fixed in the Collector. Telegraf default flush interval is 15 seconds, so a missed push of more than 20 cycles is a real problem (network down, Telegraf crashed, host shut down).

When you click a host row, the panel below shows the last received values:

Four big cards: CPU, Memory, Swap, Load Average. Each shows the latest known value (used percent for CPU/Mem/Swap, 1-minute load with 5m/15m below).

A table with one row per mount point (Linux) or drive letter (Windows), with the used percent. Color codes:

• < 75% → green
• 75-90% → orange
• > 90% → red

A table with the top processes ranked by CPU, Memory, or Disk I/O (button toggles at the top right of the panel). Up to 20 processes are listed.

• CPU % - per-process CPU usage as reported by Telegraf
• Memory - resident set size (RSS) - actual physical memory used
• Disk I/O - read and write bytes since the process started

If you do not see any process, the most likely causes are:

• The process input is not enabled in the Configuration tab → enable it and redeploy the agent
• The agent has not pushed yet → wait 30 seconds (procstat sends every 30s by default)
• On Linux Docker without SYS_PTRACE, the process list works but read/write bytes will be zero (see the process monitoring section)

• Processes - total / running / zombies (from the processes input - Linux only)
• Network - bytes sent (↑) and received (↓) per interface, in human-readable units
• First Seen - when the host was first auto-discovered

Use the Remap to System dropdown to link the host to a System (or set it back to Standalone).

• When a host is linked to a System, its metrics get the System tags automatically (sid, system name, etc.) - dashboards by System include them
• When standalone, metrics are stored with only the host tag - they still go through the pipeline but they are not associated to any System

Click Save to apply the link.

The Activate / Deactivate button (pause icon when ON, play when OFF) toggles the Active flag on the host:

• OFF rejects every incoming push from this host with 403 Forbidden
• ON accepts pushes again

Useful when you want to silence a host temporarily without uninstalling Telegraf.

Removes the host from the database. The next push from this host will re-create it as a new entry (with Standalone link, so you will need to re-map it).

Use this to clean up old hosts that no longer exist.

A Refresh button at the top of the panel reloads the host list and detail. The list does not auto-refresh - click Refresh after waiting a few seconds to see the new values.

Hosts appear automatically the first time they push successfully:

1. The Collector parses the host tag from the first metric line
2. It checks the in-memory map and the database
3. If unknown, tries to resolve a System by matching the hostname (case-insensitive) against the existing connectors
4. If it matches a connector, the host is auto-linked to that System
5. Otherwise the host is standalone

You do not need to pre-register hosts. Just install Telegraf and they show up.