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Communication between linked docker containers


(Sunnysi) #1

I have two docker containers in the following setup on a host machine:

Container 1 - UDP Port 5043 is mapped to host port 5043 (0.0.0.0:5043:5043/udp)

Container 2 - Needs to send data to Container 1 on port 5043 as UDP.

Scenario 1

I. start Container 1 and obtain it’s IP address.
2. I use this IP address and configure Container 2 with it and start it.
3. Container 2 is able to send UDP data to Container 1 by calling udp://Container_1_IP:5043

EVERYTHING WORKS!!

Scenario 2

  1. I start Container 1 by mapping 5043 UDP port to host’s 5043 port (0.0.0.0:5043:5043/udp)
  2. I link Container 2 and Container 1 using ‘–links’.
  3. Now, when Container 2 invokes the URL udp://Container_1_IP:5043, an error is thrown “Connection refused”.I did verify that I am able to ping the Container 1 from inside the Container 2 using the IP.

Any help to get the Scenario 2 working for me would be really appreciated!!