DHCP not assigning Addresses

i am using Redhat 8.0 as a gateway and can't get clients an IP address.

I am running up to date dhcpd, the service is started and configured. here is dhcpd.conf:

subnet x.x.x.x netmask { }
 # where x.x.x.x is the static, public IP assigned to external interface eth0

ddns-update-style ad-hoc;
subnet netmask {
        default-lease-time 86400;
        max-lease-time 86400;
        get-lease-hostnames on;
        option routers;
        option ip-forwarding on;
        option broadcast-address;
        option subnet-mask;
        option domain-name-servers m.m.m.m, n.n.n.n;
 #where m and n represent ns1 and ns2


i added route dev eth0
and route dev eth1
tried both, either and neither.

current route tables looks like: *      UH    0      0        0 eth1 *      UH    0      0        0 eth0     *        U     0      0        0 eth1
x.x.x.0   *        U     0      0        0 eth0       *            U     0      0        0 lo
default         rtr1080-07-vl18         UG    0      0        0 eth0

dhcpd daemon set at eth1

sooo if i assign an IP address to a client .... say and input gw address and name servers, there is no problem. But if I assign same gateway address and name servers but say get IP automatically, i get squat.I will post my iptables if you think they are necessary but the packets do get routed and the internet works as expected when an IP is assigned.

whats up?

thank you.
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subnet x.x.x.x netmask {
       option routers x.x.x.y;
# your ISP gateway

x.x.x.y is the gateway of eth0
See my comments in http://www.experts-exchange.com/Networking/Linux_Networking/Q_20559199.html as there is a lot there that may be pertinent to you as well.

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weazyAuthor Commented:

like the user you were trying to help I am able to get folks on the net when they insert the private network ip i.e. 192.168.0.x they connect no problem, use DHCP and it doesn't work. even after the changes you proposed.

ipconfig /all on the windows box shows the dhcp server address as does that have a bearing?
On the RedHat system, open a command window and do "service iptables stop". Then, try to obtain a DHCP address from a client machine.

If you still can not get an address on the client machine, there is a problem with the configuration of your DHCP server. To make sure that the server is running, and on the proper interface, do the following:

ifconfig -a

Look through the list of interfaces and determine the name of the interface that is on the Inside of your network. Make sure that the interface has an IP address. Then do:

ps -ef |grep dhcpd

Make sure that it shows the same interface name as the interface on the Inside of your network.


If you *can* get an address after turning off IPTABLES, you need to open the appropriate "hole" in the firewall to allow DHCP requests through.
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