README.md

DHCP Builder

A script to read a terraform.tfvars file and build a generic dhcpd.conf file for cluster install on VMWare vSphere hosts.

Pre-requisites

• A set of variables in tfvars identifying required data for script
  • machine cidr
  • bootstrap ip and name
    • bootstrap_name = "bootstrap-00"
    • bootstrap_ip = "10.111.111.100"
  • A mac vendor id prefix and a separate cluster id
    • The macprefix is just the VMWare mac vendor string (like 00:50:56) for the first part of the mac address
    • The cluster_mac_id should be changed for each new cluster
  • nodes names (list of node names named with a _names suffix)
    • master_names = ["master-0", "master-1", "master-2"]
    • infra_names = ["infra-0", "infra-1", "infra-2"]
    • worker_names = ["worker-0", "worker-1", "worker-2"]
    • storage_names = ["storage-0", "storage-1", "storage-2"]
  • node ips
    • master_ips = ["10.111.111.101", "10.111.111.102", "10.111.111.103"]
    • infra_ips = ["10.111.111.111", "10.111.111.112", "10.111.111.113"]
    • compute_ips = ["10.111.111.121", "10.111.111.122", "10.111.111.123"]
    • storage_ips = ["10.111.111.131", "10.111.111.132", "10.111.111.133"]
  • node count (set to 0 to disregard a node type)
    • master_count = 3
    • infra_count = 3
    • compute_count = 3
    • storage_count = 3
  • domain_name
    • domain_name =
  • search_domains
    • search_domains = ["search_domain1", "search_domain2", "search_domain3"]
  • dommain_name_servers
    • dommain_name_servers = ["10.111.111.254", "10.111.111.253"]

These variables are read in and used to build the subnet block network and netmask, the pool range, the static ip block hosts/ip/mac addresses, and the option routers line.

The idea

Build a dhcp config file from your terraform config for cluster install. This should help minimize copy/paste errors and reduce human error until CoreOS images can be built with vSphere agent to allow for static ips to be assigned using native terraform ipv4 directives before bootstrap.