Don’t expose your REDIS or SQL ports to the world, limit which Docker containers can access them ( legacy solution )

A long time ago we had a temporary security breach. It was not really fully exploited as it was a pretty shielded use-case – but it could have been, if it was used in production. When you have Docker containers that share ports with each other, some of their ports may be exposed on your […]

Update all Docker Images at once

Update ( 2018 ): As mentioned in the comments, you can by now also use the following syntax : docker images –filter “dangling=false” –format “{{.Repository}}:{{.Tag}}” | xargs -L1 docker pull This would then update all images that aren’t currently dangling ( Images that show up with <none>¬†as they aren’t used any longer. You should clean […]

Backup Docker to Amazon S3

There is a great tutorial in GIST form on how to backup MySQL Databases through a Cron Job to Amazon S3 by David King over at Github. Let’s use that to periodically backup running Docker containers to your Amazon S3 bucket as well. A word of caution: Note that with every backup we’ll do a […]

Clean up after Docker

After many build and run sessions with Dockerfiles, you’ll be mostly left with a few left-over containers, unneeded mounts and exited images. Especially if you don’t use the ‘rmi’ flag when running docker build. Find out how many images Docker has on a system You can always inspect which images are currently clogging up your […]

Breaking down a Dockerfile

A while ago after speaking with the great guys over at Rackspace, we discovered Docker, and have not looked back since. Docker allows you to create server instances in the same way you would create APPs in your application. What does that mean? It means you can run your own little Heroku or SaaS platform […]