What does failover transport do with a single URI

Question

In my ActiveMQ client when I specify which broker to which to connect, what's the difference between specifying

tcp://host:port

and

failover:(tcp://host:port)

I've tried stopping and starting the broker and in both cases the client finds the broker again when it restarts. I haven't experimented with messages in flow (I'm using queues) or other network failures yet to see if there is a difference.

Hopefully someone has a definitive answer as the documentation I've found is a bit vague.

Thanks

Answer 1

If you use failover, then the client library go into a reconnect loop when you loose connection to the server. The network failure will be hidden from your app. If you don't use failover, then when you loose your connection then your app will get a JMS error telling you you lost the connection.

Answer 2

failover protocol also lets you provide some useful connection parameters. For ex:

failover:(tcp://host:port)?jms.useAsyncSend=true&timeout=5000

Here timeout=5000 will make sure to bail out initial connection attempt after 5 sec if broker isn't available or not responding.