DevOps Classroom notes 02/Jul/2025

Docker Networking contd

• By default docker container run on bridge network (default)
• We can create our own bridge networks
• container can be connected to network even after creation.
• Lets create two containers d1 and d2 in default bridge network

docker run --name d1 -d alpine sleep 1d
docker run --name d2 -d alpine sleep 1d

* Now lets inspect container and find ip addresses. Try ping

* Default bridge network allows ip based resolution but not name based resolution
* Where a custom bridge network allow name based resolutions
* Lets create a custom bridge network with range 192.168.0.0/24

docker network create --driver bridge --subnet 192.168.0.0/24 learning

* NOw lets create two container l1 and l2 and try connectivty by name and ip

docker run --name l1 --network learning -d alpine sleep 1d
docker run --name l2 --network learning -d alpine sleep 1d

Nop Commerce with network

• We have a image called as nop:1.0 which is our application and also we have pulled mysql image
• lets create a network called as nop-net with range 10.100.0.0/24

docker network create --driver bridge --subnet 10.100.0.0/24 nop-net

• Lets create a volume for database nop-vol

docker volume create nop-vol

• Lets create a database container nopdb in nop-net with nop-vol attached

docker run \
  --name nopdb \
  --network nop-net \
  -e POSTGRES_USER=nop \
  -e POSTGRES_PASSWORD=qtdevops \
  -e POSTGRES_DB=nop \
  -p 5432:5432 \
  -d postgres

* Now lets create nop container in nop-net

docker container run -d \
    --name nop \
    --network nop-net \
    -p 80:5000 \
    shaikkhajaibrahim/febnop:latest

• To be continued to show the running version

Registry

• Registries are where we store/distribute our images
• Popular Registries
  • Docker hub
    • Private
    • Public Registries
  • Azure Container Registy (ACR)
  • AWS Elastic Container Registry (ECR)
  • GCR
  • Jfrog/Artifactory
• Registries will have repositories where each repo reprsents and application image which will have versions as tags.
• Login into registy
  • docker hub docker login
• Create a tag according to repo