linux dhcp question

Linux DHCP Problem


I need help urgently with a DHCP problem please .


On my home gateway / firewall pc Im trying to change the static /
fixed IP address for eth0 (the single network adaptor) to a
dynamic IP address using DHCP.

I need help setting up the DHCP server not the client DHCP on this
firewall pc.

The firewall pc is rehdat 8 and yes the NIC driver is loading fine
during the bootup, and has been running fine for months using a fixed
IP address for eth0.

My internet connection is a 56k PPP dial up connection so I need to
tell the DHCP server to ignore the PPP adaptor some how as well.

Now since I have others here for Lan UT games whose pc`s are running
Windows XP with a dynamic IP address for there network cards it means
I have to change my computers to DHCP .


I hope that's clear !

My friends pc is running windows XP using ICS the addresses in the
192.168.0.x range. With a 255.255.255.0 mask.


So the big question is what to I need in the /etc/dhcpd.conf file
to get this all working using DHCP on my linux firewall box ?


Many thnx !!

FreddyK wrote:
> Linux DHCP Problem
>
>
> I need help urgently with a DHCP problem please .
>
>
> On my home gateway / firewall pc Im trying to change the static /
> fixed IP address for eth0 (the single network adaptor) to a
> dynamic IP address using DHCP.
>
> I need help setting up the DHCP server not the client DHCP on this
> firewall pc.
>
> The firewall pc is rehdat 8 and yes the NIC driver is loading fine
> during the bootup, and has been running fine for months using a fixed
> IP address for eth0.
>
> My internet connection is a 56k PPP dial up connection so I need to
> tell the DHCP server to ignore the PPP adaptor some how as well.
>
> Now since I have others here for Lan UT games whose pc`s are running
> Windows XP with a dynamic IP address for there network cards it means
> I have to change my computers to DHCP .
>
>
> I hope that's clear !
>
> My friends pc is running windows XP using ICS the addresses in the
> 192.168.0.x range. With a 255.255.255.0 mask.
>
>
> So the big question is what to I need in the /etc/dhcpd.conf file
> to get this all working using DHCP on my linux firewall box ?
>
>
> Many thnx !!
>
>
>
>
>
>
>
First, about the PPP, I'm thinking that the ethernet will not see the
actual modem.
Second, I;m not sure about getting linux to a dhcp client. But something
like dhcpclient script appears in my head.
Third, ...
Fourth, Below is a /etc/dhcpd.conf file of mine, I snips some parts out
to be more simple.

#/etc/dhcpd.conf
ddns-update-style none;
default-lease-time 21600;
max-lease-time 21600;
option subnet-mask 255.255.255.0;
option broadcast-address 192.168.0.255;
server-name = "jHente";
option interface-mtu 1500;
option ip-forwarding = 0;
option non-local-source-routing = 0;
option arp-cache-timeout 600;

shared-network Local_Network_0 {
subnet 192.168.0.0 netmask 255.255.255.0 {
range 192.168.0.100 192.168.0.250;
}
}

group {
use-host-decl-names on;
option log-servers 192.168.0.254;


host firewall {
hardware ethernet 00:00:00:00:00:00
fixed-address 192.168.0.1
}
}


For the most part, this script will tell the server:
-for the host with the MAC of 00:00:00:00:00:00, give it I.P. of
192.168.0.1, like RARP... (a feature I didn't notice in Windows 2000 sp3
dhcp (but I was only looking for like a few mins.)) This will give the
computers a semi-static IP, but you can still change it.
-for the unknown MACs, give them addresses between 192.168.0.100 to
192.168.0.250 with a netmaks of 255.255.255.0

As for the client, if:
+client has MAC of 00:00:00:00:00:00 :
clint has I.P. of 192.168.0.1, netmask 255.255.255.0, arp-timeout of
600 (s or m)(set high to make it slighly more difficult to arp spoof,
but not great if the enviroment constantly changes), max. trans. unit of
1500kb, IP address renew never,
+Client has an MAc not in the dhcpd.conf, I think BIND will give it the
address of 192.168.0.100, then 192.168.0.101, 1500kb mtu, ...

It might help to have all hosts defined to be in the /etc/hosts

to start the dhcp:
# /etc/init.d/dhcpd restart


Also, I recommend that you read more on BIND. The book I learned from
is: TCP/IP network admin. (o'rielly), although $50, covers other stuff too.

On Tue, 23 Sep 2003 20:16:38 -0500, Joe Hente <(E-Mail Removed)>
wrote:

>FreddyK wrote:

>>
>>
>First, about the PPP, I'm thinking that the ethernet will not see the
>actual modem.
>Second, I;m not sure about getting linux to a dhcp client. But something
>like dhcpclient script appears in my head.
>Third, ...
>Fourth, Below is a /etc/dhcpd.conf file of mine, I snips some parts out
>to be more simple.
>
>#/etc/dhcpd.conf
>ddns-update-style none;
>default-lease-time 21600;
>max-lease-time 21600;
>option subnet-mask 255.255.255.0;
>option broadcast-address 192.168.0.255;
>server-name = "jHente";
>option interface-mtu 1500;
>option ip-forwarding = 0;
>option non-local-source-routing = 0;
>option arp-cache-timeout 600;
>
>shared-network Local_Network_0 {
> subnet 192.168.0.0 netmask 255.255.255.0 {
> range 192.168.0.100 192.168.0.250;
> }
>}
>
>group {
> use-host-decl-names on;
> option log-servers 192.168.0.254;
>
>
> host firewall {
> hardware ethernet 00:00:00:00:00:00
> fixed-address 192.168.0.1
> }
>}
>
>
>For the most part, this script will tell the server:
>-for the host with the MAC of 00:00:00:00:00:00, give it I.P. of
>192.168.0.1, like RARP... (a feature I didn't notice in Windows 2000 sp3
>dhcp (but I was only looking for like a few mins.)) This will give the
>computers a semi-static IP, but you can still change it.
>-for the unknown MACs, give them addresses between 192.168.0.100 to
>192.168.0.250 with a netmaks of 255.255.255.0
>
>As for the client, if:
>+client has MAC of 00:00:00:00:00:00 :
> clint has I.P. of 192.168.0.1, netmask 255.255.255.0, arp-timeout of
>600 (s or m)(set high to make it slighly more difficult to arp spoof,
>but not great if the enviroment constantly changes), max. trans. unit of
>1500kb, IP address renew never,
>+Client has an MAc not in the dhcpd.conf, I think BIND will give it the
>address of 192.168.0.100, then 192.168.0.101, 1500kb mtu, ...
>
>It might help to have all hosts defined to be in the /etc/hosts
>
>to start the dhcp:
> # /etc/init.d/dhcpd restart
>
>
>Also, I recommend that you read more on BIND. The book I learned from
>is: TCP/IP network admin. (o'rielly), although $50, covers other stuff too.



Thnx Joe !!