Live run monitoring

Envoy run pages combine durable run records with live WebSocket updates. The control plane publishes status changes and tails metrics and logs while an authorized browser is subscribed.

Live updates improve operator response time. They are not the durable source of truth and do not control task execution.

What updates live

Depending on the page and run type:

• task and job status transitions;
• per-step counters and rates;
• newly persisted log content;
• job task transitions.

The browser subscribes to topics for the run it is viewing. The server starts log or metric tailing when needed and stops unused tailers after subscribers leave.

Network requirements

Your reverse proxy and load balancer must support:

• WebSocket upgrade headers;
• long-lived connections;
• idle timeouts longer than expected quiet periods;
• the application's authentication cookie;
• the public origin and path used by the browser.

For multiple control-plane replicas, follow the deployment's supported event-distribution and session-routing design. Do not assume an in-memory event published on one replica is visible to a client connected to another.

Verify live monitoring

1. Start a task that runs long enough to observe.
2. Open its run page.
3. Confirm status changes without a reload.
4. Confirm metrics increase.
5. Emit several log lines and verify ordering.
6. disconnect the browser network briefly;
7. reconnect and confirm stored state catches up;
8. complete the run and reload the page.

Repeat through the production reverse-proxy path, not only against a local port.

Interpreting gaps

A quiet page can mean:

• the task is legitimately idle;
• no new metrics were flushed;
• log persistence failed;
• the WebSocket disconnected;
• a proxy timed out the connection;
• the control plane or executor lost contact.

Refresh the run and compare durable status, stored logs, heartbeat or lease state, and executor health. Do not stop or rerun a job based only on a stale browser counter.

Operational response

When a run appears stuck:

1. verify the run's durable status;
2. check the last status and log timestamps;
3. inspect control-plane and executor health;
4. confirm the external connector is responding;
5. wait for configured lease or timeout behavior where applicable;
6. stop only after considering partial external writes;
7. reconcile state before resuming or rerunning.

Data protection

Live logs can include connector and record-level errors. Use role-based access, HTTPS, and approved support-sharing practices. Do not add raw secret values to task debug output.

See Monitor and control job runs, VictoriaLogs, and Debugging reference.