Environment variables

A small number of environment variables influence how Stalwart starts. None of them are required for a normal installation; they exist for recovery, diagnostics, and clustering.

Recovery and bootstrap

The following variables control the recovery and bootstrap modes:

• STALWART_RECOVERY_MODE: enables recovery mode when set to 1 or true. Defaults to off, so Stalwart starts normally when the variable is unset or set to any other value.
• STALWART_RECOVERY_MODE_PORT: HTTP port the recovery or bootstrap listener binds to. Defaults to 8080.
• STALWART_RECOVERY_MODE_LOG_LEVEL: verbosity of the log output while the server is in recovery or bootstrap mode. Defaults to info.
• STALWART_RECOVERY_ADMIN: configures the recovery administrator in the form username:password. The same variable is also used during bootstrap to pin an administrator credential instead of relying on the randomly generated one.

Clustering

When Stalwart runs as part of a cluster, two additional variables influence how a given node participates. Both are covered in detail in the clustering documentation and are listed here for completeness, so operators know which values the binary reads from the environment:

• STALWART_ROLE: selects which cluster role the node takes on, determining which tasks and listeners are active on that machine.
• STALWART_PUSH_SHARD: assigns the node to a specific push notification shard.