Saturday, June 25, 2011

How to disable NetBIOS over TCP/IP on Windows-Clients via dhcp:

f anyone out there is trying to get rid of NetBIOS to reduce broadcast traffic and optimize their network, here are the options for ISC dhcpd.conf to fast perform this operation on a large number of computers:

# to save the vendor id in the lease db:
set vendor-id = option vendor-class-identifier;

# specifying the option space name:
option space MSFT;
option MSFT.nbt code 1 = unsigned integer 32;

# subnet declaration:
subnet 192.168.100.0 netmask 255.255.255.0 {
range 192.168.100.10 192.168.100.100;
if substring ( option vendor-class-identifier, 0, 8 ) = "MSFT 5.0"
{
vendor-option-space MSFT;
# 1 = enable, 2 = disable NetBIOS over TCP/IP:
option MSFT.nbt 2;
}
}

# single host with fixed IP:
host max {
hardware ethernet 00:90:f5:05:3b:b4;
fixed-address 192.168.100.101;
if substring ( option vendor-class-identifier, 0, 8 ) = "MSFT 5.0"
{
vendor-option-space MSFT;
# 1 = enable, 2 = disable NetBIOS over TCP/IP:
option MSFT.nbt 2;
}
}



Result from "ipconfig /all" on client:

netbios-disabled

Download the full dhcpd.conf:

http://www.bakarasse.de/pages/en/linux/disable-netbios-via-dhcp.php?lang=EN