Motivation:

I want to use my linux server instead of the average wireless router for several reasons

1. I want to learn how to set up a more complete server on linux


2. I don't want to have a modem, connected to a router, connected to a network switch


3. I am sick and tired of having to unplug my router every 10 days because it just hangs


4. I am sick and tired of buying routers only to realize they are missing something crucial, like port forwarding or static ip addressing (dhcp)

Set up:

Ultimately, the connection will come into a modem, and straight into my server through eth0, then eth1 will output to a network switch which all other client computers will connect to via ethernet cables (forget wireless for the moment). Currently, however, I am in an office building, and I have the connection coming into a modem, which goes into a router, which goes into a network switch, which then goes into eth0 as specified above.

Current Tutorials:

I looked at some tutorials (Ubuntu tutorial is the best one), and I have looked at some of the router questions here (ie. this one), but they all gloss over several key concepts, like:

• What is eth1's relation to eth0? In /etc/network/interfaces do I have to tell eth1 to use eth0 as the network (generally it is the actual physical router address)?


• Do I have to do anything to instruct eth1 to take the internet that comes into eth0 and pass it onto whoever wants it in the network switch?

Current Approach:

Here is my /etc/network/interfaces file on the server:

iface lo inet loopback



auto eth0

   iface eth0 inet static

   address 192.168.1.70

   netmask 255.255.255.0

   broadcast 192.168.1.255

   network 192.168.1.0

   gateway 192.168.1.1

   dns-nameservers 8.8.8.8



auto eth1

   # iface eth1 inet dhcp

   iface eth1 inet static

   address 192.168.7.0

   netmask 255.255.255.0

   broadcast 192.168.1.255

   network 192.168.1.0

And ifconfig tells me that both NICs are working fine:

eth0      Link encap:Ethernet  HWaddr 20:cf:30:55:a0:5f  

          inet addr:192.168.1.70  Bcast:192.168.1.255  Mask:255.255.255.0

          inet6 addr: fe80::22cf:30ff:fe55:a05f/64 Scope:Link

          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1

          RX packets:11297 errors:0 dropped:0 overruns:0 frame:0

          TX packets:16639 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:1000 

          RX bytes:948633 (948.6 KB)  TX bytes:1274685 (1.2 MB)



eth1      Link encap:Ethernet  HWaddr 00:11:95:f7:f4:6d  

          inet addr:192.168.7.0  Bcast:192.168.1.255  Mask:255.255.255.0

          inet6 addr: fe80::211:95ff:fef7:f46d/64 Scope:Link

          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1

          RX packets:243 errors:0 dropped:0 overruns:0 frame:0

          TX packets:3231 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:1000 

          RX bytes:29934 (29.9 KB)  TX bytes:213055 (213.0 KB)

          Interrupt:21 



lo        Link encap:Local Loopback  

          inet addr:127.0.0.1  Mask:255.0.0.0

          inet6 addr: ::1/128 Scope:Host

          UP LOOPBACK RUNNING  MTU:65536  Metric:1

          RX packets:5348 errors:0 dropped:0 overruns:0 frame:0

          TX packets:5348 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:0 

          RX bytes:470737 (470.7 KB)  TX bytes:470737 (470.7 KB)



wlan0     Link encap:Ethernet  HWaddr bc:f6:85:f8:70:5c  

          UP BROADCAST MULTICAST  MTU:1500  Metric:1

          RX packets:0 errors:0 dropped:0 overruns:0 frame:0

          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0

          collisions:0 txqueuelen:1000 

          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

And here is what route -n returns on the server:

Destination     Gateway         Genmask         Flags Metric Ref    Use Iface

0.0.0.0         192.168.1.1     0.0.0.0         UG    0      0        0 eth0

169.254.0.0     0.0.0.0         255.255.0.0     U     1000   0        0 eth1

192.168.1.0     0.0.0.0         255.255.255.0   U     0      0        0 eth0

192.168.7.0     0.0.0.0         255.255.255.0   U     0      0        0 eth1

Then on the client I have

auto lo

iface lo inet loopback

iface eth0 inet dhcp

But it is not being assigned an ip address.

EDIT: Here is the isc-dhcp-server configuration file located at /etc/dhcp3/dhcpd.con which I copied mostly from this site.

# Sample /etc/dhcpd.conf                                                                                                                                                  

# (add your comments here) 

default-lease-time 600;

max-lease-time 7200;

option subnet-mask 255.255.255.0;

option broadcast-address 192.168.1.255;

option routers 192.168.1.254;

option domain-name-servers 192.168.1.1, 192.168.1.2;

option domain-name "mydomain.example";



subnet 192.168.7.0 netmask 255.255.255.0 {

   range 192.168.7.10 192.168.7.25;

}  

EDIT: Output of sudo iptables -L

Chain INPUT (policy ACCEPT)

target     prot opt source               destination         



Chain FORWARD (policy DROP)

target     prot opt source               destination         

ACCEPT     all  --  anywhere             anywhere             ctstate RELATED,ESTABLISHED

ACCEPT     all  --  anywhere             anywhere            

LOG        all  --  anywhere             anywhere             LOG level warning



Chain OUTPUT (policy ACCEPT)

target     prot opt source               destination         

Question:

What crucial steps/components am I missing in this setup?