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One DHCP server serving 2 subnets

My linux box has 3 NICs:

eth0 -> connected to the Internet
eth1 -> ip:192.168.1.1
wlan0 -> ip:192.168.0.1

eth0 obtains ip thru' dhclient w/o problem.
i want to setup a DHCP server that provides IPs to clients connected via eth1 and wlan0 and they are supposed to be on 2 different subnets.

my dhcpd.conf is as follows:

Code:



subnet 192.168.1.0 netmask 255.255.255.0

{

        range 192.168.1.100 192.168.1.200;

        option subnet-mask 255.255.255.0;

        option broadcast-address 192.168.1.255;

        option domain-name-servers 123.123.123.10, 123.123.123.20;

        option routers 192.168.1.1;

}



subnet 192.168.0.0 netmask 255.255.255.0

{

        range 192.168.0.100 192.168.0.200;

        option subnet-mask 255.255.255.0;

        option broadcast-address 192.168.0.255;

        option domain-name-servers 123.123.123.10, 123.123.123.20;

        option routers 192.168.0.1;

}

the client connected via eth1 works well and can obtain an ip 192.168.1.100 successfully.

however, another client (myLaptop) connected wirelessly, via wlan0 can obtain 169.254.x.x automactically. of course, it cannot ping the gw 192.168.0.1. when i tried to manually type the ip 192.168.0.100 netmask 255.255.255.0 gw 192.168.0.1 in myLaptop, it worked then. it indicates that there is no problem for my wireless lan settings. so i guess there is some problem for the dhcp settings. how to bring it work?

did you make sure you aren't blocking the incoming and/or outgoing "DHCP packets" on the wireless interface with iptables??

Code:

iptables -I INPUT -p UDP -i wlan0 --dport 67 --sport 68 -j ACCEPT

iptables -I OUTPUT -p UDP -o wlan0 --dport 68 --sport 67 -j ACCEPT

thanks, but it still dun work

i updated the iptables, which is now:

Code:

Chain INPUT (policy ACCEPT)

target    prot opt source              destination        

ACCEPT    udp  --  anywhere            anywhere            udp spt:bootpc dpt:bootps 

ACCEPT    tcp  --  192.168.0.0/24      192.168.0.1        tcp dpt:5900 

ACCEPT    tcp  --  192.168.0.0/24      192.168.0.1        tcp dpt:microsoft-ds 

ACCEPT    tcp  --  192.168.0.0/24      192.168.0.1        tcp dpt:netbios-ssn 

ACCEPT    udp  --  192.168.0.0/24      192.168.0.1        udp dpt:netbios-dgm 

ACCEPT    udp  --  192.168.0.0/24      192.168.0.1        udp dpt:netbios-ns 

ACCEPT    tcp  --  192.168.0.0/24      192.168.0.1        tcp dpt:https 



Chain FORWARD (policy ACCEPT)

target    prot opt source              destination        



Chain OUTPUT (policy ACCEPT)

target    prot opt source              destination        

ACCEPT    udp  --  anywhere            anywhere            udp spt:bootps dpt:bootpc

the scenario remains the same......

Quote:

Originally posted by scng
thanks, but it still dun work

i updated the iptables, which is now:

Code:

Chain INPUT (policy ACCEPT) target prot opt source destination ACCEPT udp -- anywhere anywhere udp spt:bootpc dpt:bootps ACCEPT tcp -- 192.168.0.0/24 192.168.0.1 tcp dpt:5900 ACCEPT tcp -- 192.168.0.0/24 192.168.0.1 tcp dpt:microsoft-ds ACCEPT tcp -- 192.168.0.0/24 192.168.0.1 tcp dpt:netbios-ssn ACCEPT udp -- 192.168.0.0/24 192.168.0.1 udp dpt:netbios-dgm ACCEPT udp -- 192.168.0.0/24 192.168.0.1 udp dpt:netbios-ns ACCEPT tcp -- 192.168.0.0/24 192.168.0.1 tcp dpt:https Chain FORWARD (policy ACCEPT) target prot opt source destination Chain OUTPUT (policy ACCEPT) target prot opt source destination ACCEPT udp -- anywhere anywhere udp spt:bootps dpt:bootpc

the scenario remains the same......

the policies on all your chains are ACCEPT, so all of those ACCEPT rules you have are pointless... either way, the fact your firewall is totally open pretty much rules-out a firewall issue i guess... does dhcpd work properly on eth1 (192.168.1.0/24)?? oh, wait, i just re-read your post and you stated dhcpd is working well on eth1... hmmm... i'm not sure what it could be... are you using SELinux??