Reading your app's logs

When something is wrong, the app's own log is almost always the fastest answer, and it is usually written in plain language: a wrong password, a missing setting, a port already in use.

Where to find it

Open the app and choose the Logs tab. You will see the most recent output, newest at the bottom.

• Service — apps made of more than one container (an app plus its database) let you pick which one to look at. If the app will not start, check the database first; an app often fails simply because its database was not ready.
• Lines — how much history to fetch. Start small and increase it if you need more.
• Refresh — logs are fetched when you open the tab and when you press this. They do not stream continuously, so press it again after reproducing a problem.

What to look for

Read from the bottom up. The last few lines before a crash are usually the useful ones, and everything above them is often normal startup noise.

Some patterns worth knowing:

• EACCES or "permission denied" — the app could not write somewhere it expected to.
• "connection refused" naming a database — the app started before its database was ready. This often resolves itself; restart the app and look again.
• "authentication failed" after mail settings — check the credential on the Mail tab.
• Nothing at all — the container may not be running. Check the app's status on the Overview tab.

What logs do not include

Logs are what the application itself printed. They are not a record of who visited your app, and they are not kept forever — old output is discarded as new output arrives.

If you need something preserved, copy it out before it scrolls away.

When the log is not enough

The Console tab opens a shell inside the app, which is the next step for anything the log does not explain. And if you would like a second pair of eyes, open a ticket — paste the last twenty or so lines and say what you were doing.