Enum Arbitration 

pub enum Arbitration {
    Primary(Hosted),
    Secondary,
    Unavailable(String),
    InvalidAppId(InvalidAppId),
}

Variants

Primary(Hosted)

This process is the instance; keep the guard alive for the process lifetime.

Secondary

Another live instance exists and was told about this launch.

Unavailable(String)

No suite root could be resolved (fail closed on discovery, proceed without arbitration).

InvalidAppId(InvalidAppId)

The app id cannot be turned into a service name (see service_name). This is a bug in the caller, not an environment problem: arbitration did not run, so single-instance protection would be OFF if this were ignored. Never start as a second primary on it; fix the id.