Docker

• Source: https://github.com/moby/moby
• License: Apache 2.0
• Alternatives: Podman, Kubernetes, k3s

Install using the official Docker guide (NOT via Snap).

Network

The exist network is automatically created when running docker compose up. To create it manually:

docker network create --driver bridge exist

It is a plain single-host bridge network — not an overlay, and not encrypted.

Privileged Port Error

To allow binding to ports like 80 without root, add to /etc/sysctl.conf:

net.ipv4.ip_unprivileged_port_start=80

Apply immediately:

sudo sysctl -w net.ipv4.ip_unprivileged_port_start=80

Log Rotation

Docker Engine's default json-file driver never rotates, so a chatty container can fill the disk. hosting/docker-daemon/daemon.json caps it at 50 MB × 3 files:

./existential.sh run docker-daemon log-rotation

It merges into any existing /etc/docker/daemon.json (an NVIDIA host keeps its runtimes block) and then offers to restart the daemon — the log settings only apply to containers created after the restart.