Camille Fournier on ephemeral nodes in etcd

(written by lawrence krubner, however indented passages are often quotes). You can contact lawrence at: lawrence@krubner.com

I missed this the first time. In etcd a service needs to constantly update the fact that it is alive. If it dies, its info disappears. So other services can contact etcd and ask “Who is alive right now?”

ZooKeeper allows stateful connections. Thick clients. But what happens when you try to use ZooKeeper from a language that does not allow threads? Do you block on the only thread that you have?

For pub-sub she recommends RabbitMQ or ZeroMQ.

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