computer-playbook/docs/contributing/flow/debugging/network.md

Network 🌐

Docker Pull Errors 🐳

Images cannot be pulled separately, as they run inside a container.

If a docker pull or general image pull fails, it may be caused by an MTU, network, or IPv6 issue on the host PC. Check and fix accordingly:

MTU 📦

Docker defaults to MTU 1500. If the host network uses a smaller MTU (e.g. due to VPN), packets may be dropped or fragmented.

ip link show docker0
ip link show eth0

Fix via /etc/docker/daemon.json:

{"mtu": 1450}

Then restart Docker:

sudo systemctl restart docker

IPv6 🔢

If IPv6 is active but misconfigured, Docker may attempt to pull over IPv6 and fail.

ip -6 addr show
curl -6 https://registry-1.docker.io/v2/

The recommended way to disable IPv6 for local development is via Make:

make disable-ipv6

To restore the original IPv6 settings afterwards:

make restore-ipv6

Alternatively, disable IPv6 only in Docker via /etc/docker/daemon.json:

{"ipv6": false}

General Connectivity 🔌

ping -c 3 registry-1.docker.io
curl -v https://registry-1.docker.io/v2/

Check firewall rules, proxy settings, and DNS configuration.