Monitor Configuration
Monitor configurations define how Stylus tests your infrastructure components. Each monitor consists of a test script that runs on a schedule and reports the status back to Stylus.
Monitor Types
Stylus supports several types of monitors:
- Standard Monitor - Single test for a single host
- Group Monitor - Single script that updates multiple monitors
- SNMP Monitor - Network device monitoring via SNMP
- Ping Monitor - Network connectivity monitoring via ping
Logging
Output from the test's standard output and standard error streams are captured and available from the logging endpoint.
Monitor States
The state of a monitor is determined by the return value of the test script or manually set by scripts/expressions. The six states, in order of precedence, are:
| State | Description | How it's set | |
|---|---|---|---|
| Red | 🔴 | Tests that fail by returning a value other than zero | Automatic (exit code ≠ 0) |
| Orange | 🟠 | Warning state | Manual (scripts/expressions) |
| Yellow | 🟡 | A test that has timed out | Automatic (timeout) |
| Blue | 🔵 | Highlight state | Manual (scripts/expressions) |
| Green | 🟢 | Tests that return zero (success) | Automatic (exit code = 0) |
| Blank | ⚪ | A test that has not run or completed yet | Automatic (initial state) |
Metadata
Tests scripts may also set metadata associated with the run. More information on this is available in Advanced Configuration.
Testing Your Configurations
Since monitor scripts with metadata can be tricky to get right, Stylus includes a stylus test command that lets you develop your test script interactively. The output shows your script's stdout and stderr, plus the parsed monitor state as JSON, and the final rendered CSS.