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I built two docker applications that communicate with each other using the docker network, but when I tried to run those applications using nomad. The problem within nomad is that the container name is not configurable and gives the container a random name. So I can't add those containers to the docker network and have them know each other with their specific names.

So how can I run two or more docker containers in the same docker network using nomad?

Samaheen
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1 Answers1

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I'm aware of few approaches. First one works with nomad only, the others assume that consul is deployed as well.

  1. Place both containers in the same task group. Nomad will locate them always on the same node and you can access address via Nomad env variables NOMAD_IP_<label>, NOMAD_PORT_<label> or NOMAD_ADDR_<label>.

  2. Register the server application (docker container) in the consul service registry with nomad service stanza. You can then use nomad template stanza in "client" application to render config. Example/doc is here.

  3. Setup consul connect (service mesh) in your deployment.

  4. You could use consul DNS interface. Consul can work as a DNS server and every service is resolvable at <service_name>.service.<dc>.consul (doc). But you have to configure your servers to use consul DNS (doc).

Approach 1 is the easiest but has huge limitation (the same node). Approach 2 worked for me well for several years. Nomad is that intelligent that it will reload/restart your client IP should the server IP/port change.

Martin Svorad
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