Docker compose DNS resolution
Docker Compose relies on an internal DNS server to manage and resolve service names across containers within a network. Each container’s /etc/hosts file contains basic entries for local resolution, but inter-container communication is primarily handled through Docker’s internal DNS. Each container is assigned a hostname that matches the service name defined in the docker-compose.yml file. Docker’s internal DNS server keeps track of these hostnames and their corresponding container IP addresses. When a container needs to resolve another service’s name, it queries the internal DNS server. Custom entries can be added to the /etc/hosts file of containers using the extra_hosts option in the docker-compose.yml file. This allows you to define additional hostname-to-IP address mappings that will be included in each container's /etc/hosts file. How works extra_hosts: The extra_hosts option allows you to specify additional hostname-to-IP address mappings. Each entry is defined in th...