Description

Data bag and environment drivent DHCP server.

• Supports setting up Master/Master isc DHCP failover.
• Includes Support for ddns
• Includes LWRPs for managing hosts, groups and subnets.

Large parts were borrowed from work initially done by Dell, extended by Atalanta Systems and reworked by Matt Ray and Opscode. Big thanks to all of them.

Requirements

Tested on Ubuntu 12.04 CentOS 6 using Chef 10+

Limitations

• only setup to handle ipv4
• no generic classification support
• ddns is tied to dns_zones databags

Recipes

default

Stubb recipe that does nothing. Good for including LWRP's but not the other recipe stuffs.

server

The node will install and configure the dhcp-server application. Configuration is through various dhcp_X bags, and the current role/environment

Node Attributes

Allmost everyone of the parameters and options are able to be overode in the host/group/network scope these are general defaults for the server.

Check out the man page for details on dhcpd.conf options/params.

Attribute - Type - Default

node[:dhcp][:hosts_bag] - String - "dhcp_hosts"

The name of the data bag that holds host items

node[:dhcp][:networks_bag] - String - "dhcp_networks"

The name of the data bag that holds network items

node[:dhcp][:groups_bag] - String - "dhcp_groups"

The name of the data bag that holds group items

node[:dhcp][:hosts] - Array - []

The list of hosts items that this server should load

node[:dhcp][:groups] - Array - []

The list of group items this server should load

node[:dhcp][:networks] - Array - []

The list of network items this node shoul load

node[:dhcp][:interfaces] - Array - []

The Network Interface(s) to listen on. If an empty list then we will listen on all interfaces.

node[:dhcp][:failover] - Boolean - false

Enable Failover support buy setting to true

node[:dhcp][:allows] - Array - [ "booting", "bootp", "unknown-clients" ]

Set global Dhcpd allow entries

node[:dhcp][:options] Global Options

node[:dhcp][:options]['domain-name-servers'] - String - "8.8.8.8, 8.8.4.4"

List of dns servers to send to clients in the global scope

node[:dhcp][:options]['host-name'] - String " = binary-to-ascii (16, 8, \"-\", substring (hardware, 1, 6))"

Options for global scop host-name settings. The default here will generate a host as mac address if the node doesn't provide a hostname or is not defined in dns/hosts/groups.

node[:dhcp][:options]['domain-name'] - String - "\"#{domain}\""

Set domainname in the global scope to this nodes domain

node[:dhcp][:parameters] Global Parameters

These are all just k/v entries in the global params hash. All values are type: String

node[:dhcp][:parameters]["default-lease-time"] - String - "6400"

Set the default lease time in the global scope

node[:dhcp][:parameters]["ddns-domainname"] - String - ""#{domain}""`

Set the ddns domain to this nodes domain

node[:dhcp][:parameters]["ddns-update-style"] - String - "interim"

ddns Upadte style

node[:dhcp][:parameters]["max-lease-time"] - String - "86400"

Max Lease time

node[:dhcp][:parameters]["update-static-leases"] - String - "true"

Make sure we push static ip adresses defined in groups/hosts to the dns server

node[:dhcp][:parameters]["one-lease-per-client"] - String - "true"

When a client requests an ip it will release any held leases.

node[:dhcp][:parameters]["authoritative"] - String - ""

This setting has no value on purpose thats how isc-dhcpd wants it.

node[:dhcp][:parameters]["ping-check"] - String - "true"

Enable Adress collision checking

node[:dhcp][:parameters]["next-server"] - String - "#{ipaddress}"

Set this server as the global next-server

node[:dhcp][:parameters]["filename"] - String - '"pxelinux.0"'

For tftp file name Note: the quotes are nessicary for this option in the fall throught to dhcpd config.

Platform Default Attributes

RHEL

node[:dhcp][:dir] - String - "/etc/dhcpd"

node[:dhcp][:package_name] - String - "dhcp"

node[:dhcp][:service_name] - String - "dhcpd"

node[:dhcp][:config_file] - String - "/etc/dhcp/dhcpd.conf"

on RHEL < 6 it defaults to "/etc/dhcpd.conf

node[:dhcp][:init_config] - String - "/etc/sysconfig/dhcpd"

Debian

node[:dhcp][:dir] - String - "/etc/dhcpd"

node[:dhcp][:package_name] - String - "isc-dhcp-server"

node[:dhcp][:service_name] - String - "isc-dhcp-server"

node[:dhcp][:config_file] - String - "/etc/dhcp/dhcpd.conf"

node[:dhcp][:init_config] - String - "/etc/default/isc-dhcp-server"

Data Bags

Data bags drive the lionshare of the dhcp configuration. Beyond the global settings. It is not required to configure any bags other than dhcp_networks to get up and running, But if you want to statically map a network or have handy Host names provisioned by dhcp you will have to add either dhcp_groups/dhcp_hosts bags and items.

You can generate example bags by using these handy commands

% knife data bag create dhcp_networks
% knife data bag create dhcp_groups
% knife data bag create dhcp_hosts
% knife data bag from file dhcp_networks examples/data_bags/dhcp_networks
% knife data bag from file dhcp_groups examples/data_bags/dhcp_groups
% knife data bag from file dhcp_hosts examples/data_bags/dhcp_hosts

dhcp_networks

Looked up via node[:dhcp][:networks_bag]. Describes networks this dhcp server should be configured to provide services for. Per-network options can be provided as an array of strings where each string is a dhcp option. Make sure you escape "'s properly as dhcpd is touchy about the format of values.

{
  "id": "192-168-1-0_24",
  "routers": [ "192.168.1.1" ],
  "address": "192.168.1.0",
  "netmask": "255.255.255.0",
  "broadcast": "192.168.1.255",
  "range": "192.168.1.50 192.168.1.240",
  "options": [ "next-server 192.168.1.11" ]
}

dhcp_groups

Looked up via `node[:dhcp][:grougroups] Items for this bag are group entries as per the man page. Groups are sets of machines that can be configured with common parameters. A group can be bare. I.e. Contains no host or parameters entries whatsover, and just defines options.

The only required key in a host def is the "mac": key. Everything else is optional

Example Group Bag { "id": "test", "pxe": "ubuntu-precise", "parameters": [ "use-host-decl-names on", "max-lease-time 300", "default-lease-time 120", "next-server "someplace"" ], "hosts": { "some-vm": { "parameters": [ ], "mac": "11:22:33:44:55:66", "ip": "192.168.1.111" }, "another-host": { "mac": "22:33:44:55:66:77" } } }

There are a few keys that merit more discussion:

"hosts": key dhcp_group Items

Groups in isc-dhcp can define lists of hosts. In this example we are using the use-host-decl-names on tell dhcp to use the "some-vm" and "another-host" entries as the host-name for these clients. As well as setting other per-group parameters.

Each Host in the hosts Hash can have a number of settings, but the only required setting is "mac": the mac address for the host.

"mac":

mac address of this host

"ip":

ip address of this host

"parameters":

an array of isc-dhcpd parameters as-per the global parameter setting.

"pxe":

This key is used by my pxe cookbook to figure out what pxe item you want this group to boot too. That Pxe cookbook should be released soon (hopefully).

dhcp_hosts

Dhcp hosts bag is looked up via node[:dhcp][:hosts_bag], and contains Host Items.

Example Most Basic host:

{
  "id": "vagrant-vm",
  "hostname": "vagrant.vm",
  "mac": "08:00:27:f1:1f:b6",
}

Example Complex host:

{
  "id": "pxe_test-vm",
  "hostname": "pxe_test.vm",
  "mac": "08:00:27:8f:7b:db",
  "ip": "192.168.1.31",
  "parameters": [ ],
  "options": [ ],
  "pxe": "ubuntu-precise"
}

Resources/Providers

dhcp_host

Manipulate host entries in dhcpd

Actions

• add - default
• remove

Paramaters

• hostname - String
• macaddress - String
• ipaddress - String
• options - Array - []
• parameters - Array - []
• conf_dir - String - "/etc/dhcp"

Example

Add a Node

dhcp_host "myhost" do
  hostname   "somebox.foobar.com"
  macaddress "08:00:27:f1:1f:b6"
  ipaddress  "192.168.1.22"
  options   [ "domain-name-servers 8.8.8.8" ] 
end

Remove a node

dhcp_host "myhost" do 
  action :remove
  hostname "somebox.foobar.com"
end

If you undefine an entry it will also get removed.

dhcp_group

Actions

• add - default
• remove

Paramaters

• name - String - :name_attribute
• hosts- Hash - {} - This is a hash of host entries that follow the host-databag format. See the example entry in examples directory
• parameters - Array - []
• conf_dir - String - "/etc/dhcp" - The directory where the config files are stored

Example

hosts_data = { 
  "some-vm"=> {"parameters"=>[], "mac"=>"11:22:33:44:55:66", "ip"=>"192.168.1.111"},
  "another-host"=>{"mac"=>"22:33:44:55:66:77"}}
}

group "some_group" do
  parameters [ "default-lease-time 120", "next-server \"someplace\""]
  hosts hosts_data
end

dhcp_subnet

Actions

• :add - default
• :remove - default

Paramaters

• subnet - String - :name_attribute - The network subnet
• broadcast - String
• netmask - String -
• routers - Array - []
• options - Array - []
• range - String
• peer - String - nil - Peer server for this segment
• conf_dir - String - "/etc/dhcp"

Example

dhcp_subnet "192.168.1.0" do 
  range "192.168.1.100 192.168.1.200"
  netmask "255.255.255.0"
  broadcast "192.168.1.255"
  options [ "next-server 192.168.1.11" ]
  routers "192.168.1.1"
end

License and Author

Author:: Jesse Nelson ([email protected]) Author:: Matt Ray ([email protected])

Copyright:: 2012 Jesse Nelson Copyright:: 2011 Atalanta Systems Copyright:: 2011 Dell, Inc. Copyright:: 2011 Opscode, Inc.

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.