Auxiliary Servers

An auxiliary server is an FTL server that you designate and configure for a specialized purpose, and do not designate in the list of core.servers. For example, an auxiliary server might provide an eFTL service to expand capacity, or a backup bridge service for fault tolerance, or provide a persistence service in a disaster recovery model.

Auxiliary servers are optional. In many ordinary situations you do not need any auxiliary servers.

You can add auxiliary servers without restarting core servers, so auxiliary servers are ideal for expanding the client capacity of eFTL services.

An auxiliary server does not participate in a quorum.

An auxiliary server does not provide a group service.

An auxiliary server cannot provide a message broker.

Specify auxiliary servers in the servers section of the FTL server configuration file. For each auxiliary server, include an ftl configuration map, in which you specify its host and port location.

Do not include auxiliary servers in the core servers map. In the following example, notice that the auxiliary server ftl4 is not in the core servers map. 

globals:  # These values apply to all servers.

    core.servers: # The set of core servers and their locations.
        ftl1: host1:8585
        ftl2: host2:8585
        ftl3: host3:8585

servers:

    ftl1:
    # ...

    ftl4: # Aux server to expand eFTL capacity and backup bridge service.
        - ftl:
            server: host4:7890
        - eftl: {}
        - bridge: {}