Router config: set peers_failover_brokering to false

[JEnoch]

In Zenoh, the routing.router.peers_failover_brokering configuration is by default set to true.

This setting makes a router to route the messages between 2 peers, until it detects (via gossip scouting) that they are directly inter-connected with each other. For other use cases than ROS, it makes sense to have this configuration enabled by default in case some peers cannot establish direct connections.

But in ROS default configuration, all Nodes are running on the same host and will establish direct connections with each other. If some Nodes are running on a distinct hosts, they could:

• either rely on a co-localized router to communicate with the robot's nodes (peer-router-router-peer connection)
• either be configured in "client" mode connected to the robot's router (client-router-peer connection, e.g. for RViz)

Thus, for ROS having peers_failover_brokering: true serves no purpose and has some drawbacks related to the additional management overhead by the router and extra messages during the Nodes startup.

[clalancette]

Makes sense to me, thanks for the detailed explanation.