Docker networking
- docker network subcommand has options to deal with docker network
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docker has following network drivers
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The default network driver is bridge, i.e. when you create containers the contianer will be part of default docker network
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The default bridge network allows containers to communicate over ip but name resolution cannot be done
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The name resolution is possible when you create your own bridge network
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Host driver means your container gets an ip of the host
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Generally when we create a network you can also specify network range
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Docker also supports multi host network using docker swarm and the network driver will be overlay.
Scenario
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I have the following application
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The idea is to run this application in containers
- webstore => reactjs application
- storeapi => fastapi
- db => postgresdb
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We need to build docker images for
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We need to ensure the containers can communicate with each other which requires us to create network
- Generally identifying by name is more sensible
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We have a database i.e. it will store data which requires us to deal with volumes
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Steps:
- create network
- create volume
- launch containers one by one
- Roughly the commands to create
docker network create -d bridge store_net
docker volume create store_vol
docker run -d -v store_vol:/var/lib/psql --name storedb --network store_net postgres:19
docker run -d --name storeservice --network store_net storeservice:1.0
docker run -d --name webstore -P --network store_net webstore:1.0
- Now if we get new code changes
# rebuild images
docker image build -t storeservice:1.1 src/service
docker image build -t webstore:1.1 src/frontend
docker rm -f webstore storeservice
docker run -d --name storeservice --network store_net storeservice:1.1
docker run -d --name webstore -P --network store_net webstore:1.1
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Refer Here for additional networking references
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Exercise: Create contianers with specific cpu and ram Refer Here
