ISC DHCP Server example config for provisioning Snom phones

Here is an example configuration for the ISC DHCP server.

Snom VoIP phones will be detected by their MAC address (starting with 00:04:13). The DHCP server will then add the GS3 provisioning URL.

In this example is:

192.168.x.1 = GS3

192.168.x.254 = Gateway / DNS / NTP-Server

# option definitions common to all supported networks...
option domain-name "example.local";
option domain-name-servers 192.168.x.254;

option ntp-servers 192.168.x.254;

option broadcast-address 192.168.x.255;

option routers 192.168.x.254;

default-lease-time 86400;
max-lease-time 604800;

# If this DHCP server is the official DHCP server for the local
# network, the authoritative directive should be uncommented.
authoritative;

# Use this to send dhcp log messages to a different log file (you also
# have to hack syslog.conf to complete the redirection).
log-facility local7;

subnet 192.168.x.0 netmask 255.255.255.0 {
  range 192.168.x.100 192.168.x.150;

  # Snom-Phones, MAC starts with 00:04:13
  if binary-to-ascii(16, 32, "", substring(hardware, 0, 4)) = "1000413" {
    log(info, "request from snom phone, setting proper options.");
    # GS3
    option tftp-server-name "http://192.168.x.1";
    option bootfile-name "/gemeinschaft/prov/snom/settings.php?mac={mac}";
  }
}