LastSeenDocs

Troubleshooting

Answers to the things that most often go wrong, starting from what you see.

It says late, but the job ran #

  • Did the heartbeat arrive? The monitor's page shows its last heartbeat and history. If nothing arrived, run the ping by hand (curl -v https://ping.lastseen.io/YOUR-KEY) on the machine that runs the job.
  • Is the interval right? It should match how often the job really runs, not how often you'd like it to.
  • Does the job ping when it finishes? A job that varies in length needs grace to cover its longest run.
  • On a schedule: check the timezone. A server on UTC running 0 2 * * * runs at 02:00 UTC, whatever your own clock says.

The ping answers 404 #

unknown ping key: no monitor has that key. Check it's copied whole (26 characters). If the key was rotated, the old one stopped working at once: the monitor's page shows the current one, to admins.

The ping answers 429 #

The monitor is pinging more than 2 times a minute. Ping less often: once per interval is enough. The answer's Retry-After says how long to wait.

An email alert didn't arrive #

  • Is the channel ok on Channels? An address gets nothing until its owner confirms it (the confirmation link works for 24 hours; Resend verification sends another).
  • Check spam, and allow alerts@lastseen.io.
  • If the address bounced or reported spam, or someone used Turn off these alerts, the channel shows failing with the reason.
  • If the organization reached its daily alert limit, alerts wait until 00:00 UTC.

A channel shows failing #

The reason is shown under its name. A webhook, Slack or Discord URL that's been deleted answers 404, and LastSeen stops trying it. Fix the target (delete the channel and add it again with the new URL), then Send test.

A website check fails from one region #

With several regions, one failing region makes the check degraded, not down: it's shown, not alerted on. Often it's a network path between that region and your site. If it lasts, check your firewall or CDN isn't blocking that part of the world, or requests from LastSeen-Monitor/1.

I got an "unstable" alert #

The monitor went down and came back several times in a few minutes, so LastSeen stopped alerting on each change. See Flapping. Usually it's a device with weak Wi-Fi or a job that fails intermittently.

Still stuck? #

Open a ticket from Support in the app. It notes the page you were on, and we reply by email.