Restart the container with a restart policy of always so that if the container exits, Docker will restart it. Docker 1.12 introduced the docker run command: restart for this use case.
If not, then you might want to restart the container based on the exit code of the container’s main process, or always restart (regardless the exit code). If you are using a Docker orchestration engine, like Swarm or Kubernetes, the failed service will be restarted automatically. In some cases, you can fix it by re-running the failed container. When running a process inside a Docker container, a failure may occur due to multiple reasons. # create net-tools container and attach it to mynet overlay networkĭocker run -it -rm -net=mynet net-tools sh # create an attachable overlay networkĭocker network create -driver overlay -attachable mynet
The attachable option enables manual container attachment. You can use the docker run command for this, eliminating the need to create a completely new debug service.ĭocker 1.13 brings a new option to the docker network create command: attachable. Sometimes you need to attach a new Docker container (filled with different networking tools), to an existing overlay network, in order to inspect the network configuration or debug network issues. When you create a new swarm service, you can attach it to the previously created overlay network. Using Docker Engine running in swarm mode, you can create a multi-host overlay network on a manager node.
The target container can be specified by id or name. The new container will attach to the same network interfaces as the other container. Don't do this :) Use Another Container’s Network Stack $ docker run -net=container. taking over the hosts network stackĭocker run -net=host allows reusing the network stack of the host. You can just use jq to extract the desired values: # list IP addresses for all containers connected to 'bridge' networkĭocker network inspect bridge -f '' ĭocker tries to detect conflicts and will use a different subnet if needed. Just pipe docker ps output to less -S so that the table rows are not wrapped:ĭocker logs won't watch the logs by default unless use the -f flag:ĭocker logs -f Pretty Json from docker inspectĭocker inspect spits out a lots of JSON by default. Most of you are probably familiar with many of this commands, but I hope that you find one or two little nuggets from this post CLI nice docker ps output In this post I'll share with you some cool docker hacks and tips.
It's by far the sparkling unicorn of containerization happening in the world of software development and the amazing tool that simplified the configuration of our projects tenfold. Connecting by the IP address will time out: :/# curl 172.23.0.Docker is one of the amazing tools I like the most. Mind that we can't connect to the “test3” container because it's in a different network. Docker's builtin DNS service will resolve the address for us: :/# curl test2:8080 Since we're inside the Docker's network, we can also use the alias instead of the IP address. Then, use curl to send a request to the “test2” container: :/# curl 172.22.0.2:8080 Communication Between Containersįirst, let's get inside the “test1” container: $ docker exec -it b09a8f47e2a8 /bin/bash All of these examples use the docker inspect command, but many other CLI commands have.
First, let's list all containers with their identifiers: $ docker ps -format 'table 'Īlternatively, we can print hosts directly from a container using the docker exec command: $ docker exec 78c10f03ad89 cat /etc/hostsġ72.23.0.3ė8c10f03ad89 5. Docker provides a set of basic functions to manipulate template elements. The problem with jq is that it doesnt come preinstalled in most of the Linux distributions, while the default formatting mechanism of docker. inspect is already there, and it is very powerful.ocker uses go-templates to format its output. Similarly, we can inspect a specific container. Display detailed information on one or more networks.