Unveiling Whiteout Files: Do you know how file deletions are handled between layers of a Docker image?

Unveiling Whiteout Files: Do you know how file deletions are handled between layers of a Docker image?
Union file systems are a mechanism for merging two or more file systems, to present them unified, under a single mount point for the user. The main idea behind this mechanism is to be able to alter the contents of the first file system (e.g. the contents of a CD-ROM) by writing all changes (additions, deletions, modifications) to the second (which could be a disk partition, a USB stick, …). [Read More]

Give IPv6 connectivity to its Docker containers using an IPv6 block from its ISP

It may seem surprising that a modern service like Docker does not offer IPv6 in containers by default, especially when in a network with IPv6. In fact, for the same reason we saw in the introductory article, since the containers are in a virtual network, they cannot be reached by the box/router distributing the IPv6 subnet. The same phenomenon can be observed with IPv4: each container has an IPv4 in a subnet separate from the one in which our host machine is located. [Read More]