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Old 01-29-2009, 02:09 AM   #1
Registered: Oct 2007
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How to Distribute IP from DHCP Server more then 255 Usres


I have linux dchp server. I want to configure IP disributing from dchp server for 300 users.
In the dchp server, I can assign only 254. but how to setup for next users.
please help me.

Deepak Kumar

Last edited by deepak_message; 01-29-2009 at 03:35 AM.
Old 01-29-2009, 02:20 AM   #2
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adjust the netmask
Old 01-29-2009, 03:34 AM   #3
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Can you tel me in the below file, what and where should I change ..........

ddns-update-style interim; # Required for dhcp 3.0+ / Red Hat 8.0+
ignore client-updates;

subnet netmask {

range; # Range of IP addresses to be issued to DHCP clients
option subnet-mask; # Default subnet mask to be used by DHCP clients
option broadcast-address; # Default broadcastaddress to be used by DHCP clients
option routers; # Default gateway to be used by DHCP clients
option domain-name "";
option domain-name-servers,; # Default DNS to be used by DHCP clients
option netbios-name-servers; # Specify a WINS server for MS/Windows clients.
# (Optional. Specify if used on your network)

# DHCP requests are not forwarded. Applies when there is more than one ethernet device and forwarding is configured.
# option ipforwarding off;

default-lease-time 21600; # Amount of time in seconds that a client may keep the IP address
max-lease-time 43200;

option time-offset -18000; # Eastern Standard Time
# option ntp-servers; # Default NTP server to be used by DHCP clients
# option netbios-name-servers;
# --- Selects point-to-point node (default is hybrid). Don't change this unless you understand Netbios very well
# option netbios-node-type 2;

# We want the nameserver "ns2" to appear at a fixed address.
# Name server with this specified MAC address will recieve this IP.

host ns2 {
hardware ethernet 00:02:c3:d0:e5:83;

# Laser printer obtains IP address via DHCP. This assures that the
# printer with this MAC address will get this IP address every time.

host laser-printer-lex1 {
hardware ethernet 08:00:2b:4c:a3:82;
Old 01-29-2009, 08:07 AM   #4
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At the minimum, you would need to change to then you would need to adjust the scope

it-lenny:~# ipcalc

Address:          11000000.10101000.0000000 0.00000001
Netmask: = 23   11111111.11111111.1111111 0.00000000
Wildcard:            00000000.00000000.0000000 1.11111111
Network:       11000000.10101000.0000000 0.00000000
HostMin:          11000000.10101000.0000000 0.00000001
HostMax:        11000000.10101000.0000000 1.11111110
Broadcast:        11000000.10101000.0000000 1.11111111
Hosts/Net: 510                   Class C, Private Internet
I would suggest you go to and learn about subnetting.. Kinda important if you are going to be managing large networks..


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