I've tried to start a single cluster 4 times on Databricks Community Edition today (13 March 2022). It's failed every time. Here's the first part of the output summary.

```

Time

2022-03-13 13:59:14 EDT

Message

Cluster terminated.Reason:Unexpected launch failure

An unexpected error was encountered while setting up the cluster. Please retry and contact Databricks if the problem persists.

Internal error message: com.databricks.backend.manager.instance.InstanceHolder$PlacementLockTimeout: Could not acquire placement lock context = requestResourcePlacement.

```