I have a simple Docker compose file as below:
version: '3'
services:
server:
build: ./server
networks:
- common
ports:
- "4840:4840"
container_name: open62541_server
hostname: open62541-server
client:
build: ./client
depends_on:
- server
container_name: open62541_client
networks:
- common
networks:
common:
When I run it, I get the following error:
Attaching to open62541_server, open62541_client
open62541_server | [2019-06-27 12:19:54.864 (UTC+0000)] info/network TCP network layer listening on opc.tcp://open62541-server:4840/
open62541_client | [2019-06-27 12:19:55.590 (UTC+0000)] warn/network DNS lookup of open62541-server failed with error Name or service not known
open62541_client exited with code 0
Even after specifying that the containers belong to a common network, why is that I get this error? Is there anything I'm missing?
You should use server (service name) as host to which you connect within docker-compose network instead of open62541-server as neither container_name nor hostname section in docker file affects docker-compose's internal DNS.
You probably have a typo in the config file. hostname is open62541-server and container_name is open62541_server (with underscore). You should be able to connect to server with either the service name (i.e. server) or container_name (i.e. open62541_server)