I have a cluster configuration in which only a subset of nodes have access to an external resource (via private subnet). I'd like to specify that certain spouts or bolts should only be placed on those nodes, and also that certain other spouts/bolts should be excluded from those nodes.
Is there a way to define node groups or other affinity that can be specified in the topology builder ? Also, I have an external resource that requires a single master client instance to coordinate access by all other client instances. Is there a recommended way to implement support for this in a topology ? Is there sufficient metadata available in the topology context that all instances of a given bolt can nominate a single instance to be the master, and the master can communicate its listen port to the other instances ? Or is some other persistent solution required (eg, using an external object store to reflect the instance coordination) ? TIA, Dean Arnold
