Troubleshoot telemetry
Start small: one canister, one metric, a short range. Then widen until the problem appears. An error’s Details and a panel’s Evidence usually name the cause.
A chart is empty
Section titled “A chart is empty”Check, in order:
- The workspace. History belongs to one Agent. Is it the right one?
- The canister. Is it in this workspace, and has Monitor read it since you added it?
- The metric. Pick it from the metric browser rather than typing its name.
- The range. Was the canister monitored during that period?
- The rate window. A rate over a window shorter than the reading
interval is empty. Try
[30m].
An empty result means nothing was recorded. It never means zero.
A query is too heavy
Section titled “A query is too heavy”The Agent answers queries within a fixed amount of work. If a query is too heavy:
| Try | When |
|---|---|
| Fewer canisters, exact names instead of a broad regex | Too many series |
| A shorter range | Too much history |
| A simpler expression | One evaluation is too expensive |
icLens already splits heavy range queries into smaller pieces where it can.
Data from your code isn’t arriving
Section titled “Data from your code isn’t arriving”- Open the data connection’s Senders. Does your canister say Receiving, or Waiting for first data?
- Check that your canister is allowed to send: Add a sender in the connection.
- A sender that is told to slow down keeps its data and retries. Make sure your code handles that rather than dropping it.
Send telemetry from your code.
Good to know
Section titled “Good to know”- A precision notice means a very large number was rounded for PromQL. A panel’s Evidence keeps the exact value.
- An access error means your role or the workspace changed. It’s not a reason to read from another workspace.
- Clearing old data doesn’t change past reports.
When asking for help, share the workspace, metric, range, query and error code. Never share your recovery phrase or credentials.