After playing Docker for some time (including adding these tweaks for boot2docker installation), I found some more pitfalls tips for Docker/boot2docker:

  • boot2docker is based on Tiny Core Linux, which runs entirely in memory, so almost every change you made are gone when the boot2docker VM reboots. 1
  • I said almost because when the boot2docker VM starts, it will automatically mount the harddisk (/dev/sdX) and softlink 2 directories to it (/var/lib/docker, /var/lib/boot2docker), anything resides in these 2 directories are persisted (most notably the docker images and containers). 2
  • /var/lib/boot2docker/bootlocal.sh gets automatically executed when the boot2docker VM boots, so it’s the appropriate place for you to do some customization of your boot2docker VM. 2
  • If you are using self-signed certificates for your private Docker registry, as you may have expected, you have to add its certificate(s) as trusted (note that if it’s a certificate chain, you have to add all the certificates in the chain) in boot2docker or Docker or OS level (if you are using Linux). There are several ways:
    1. Copy the certificates to /etc/docker/certs.d/ (boot2docker only, can use /var/lib/boot2docker/bootlocal.sh to accomplish)
    2. Append the certificates to /etc/ssl/certs/ca-certificates.crt (boot2docker only)
    3. Use irgeek’s hashing script here: https://gist.github.com/irgeek/afb2e05775fff532f960 (boot2docker only)
    4. Use your OS’s commands to add: [https://docs.docker.com/registry/insecure/]3

    After you’ve finished adding them, restart Docker or boot2docker VM for the changes to take effect

References:

  1. https://github.com/boot2docker/boot2docker/blob/master/README.md ↩

  2. https://github.com/boot2docker/boot2docker/issues/347 ↩ ↩2

  3. https://docs.docker.com/registry/insecure/ ↩