How to create custom network with specific subnet and IP range


Create a custom network with default bridge driver named as my-custom-net with subnet gateway and IP range
Create a container named as net-test with custom network i.e my-custom-net.
Inspect the container net-test and check the IP address assigned to it.

1. Create a custom network with custom IP settings.

#docker network create --subnet --gateway --ip-range --driver bridge --label host2net my-custom-net                             

2. Inspect the custom network.

#docker network inspect my-custom-net                                                           

Check the Subnet, Gateway, IP Range and Label assigned to the network.

3. Launch the container with the custom network.  

#docker run -itd --name test1 --net my-custom-net centos:centos7 bash             

4. check container IP with docker inspect command.

#docker container inspect test1| grep -w "IPAddress"                                         

How to Access Docker container from another container by name


Create custom network with default bridge driver named as my-custom-net.
Create two container named as web1 and test1 with custom network i.e my-custom-net.
Access the container web1 from test1 using the curl command. 

1. Create a custom network with the default driver.

#docker network create --driver bridge my-custom-net                                       

2. Create Nginx Container with a custom network.

#docker container run -itd --name web1 --network my-custom-net nginx             

3. Create another container with to test Nginx container

 #docker container run -itd --name test1 --network my-custom-net                      pranavdhopey/goinit_hub:curl                                                                           

Note: pranavdhopey/goinit_hub:curl is my own image with a curl package installed on alpine base image.

4. Now check whether we are able to access the web page from other container.

#docker container exec test1 curl web1:80                                                        

By above screenshot, we can see that we are able to access web1 from test1 container using name.