DNS

This section described how dnsmasq is configured to provide DNS, DHCP and PXE Gateway services.

To understand and troubleshoot DNS please see Services / DNS section.

Example dnsmasq.conf

PXE Configuration

TBD

cluster.home Domain

The dnsmasq service can use the hosts /etc/hosts file to resolve LAN domain names. So the ansible playbook gateway-install will add a set of cluster.home domains.

The dnsmasq service is also configured to expand host names on the local subnet so “flamenco” will become “flamenco.cluster.home”.

These local FQDN cluster domain names are used to connect services and in self-signed certificates such as “registry.cluster.home” for the Docker Registry.

DHCP

The DHCP service is quite restrictive and only provides IP Addresses to known (MAC Addresses) in the cluster subnet. This ensures clients aren’t accidentally routed to the PXE Ubuntu Installer (which is destructive) or accidentally provision a non-kubernetes node in the cluster.