Hi,

I’m building a firewall/router on Centos.  I’m using Shorewall but have currently stopped and cleared the firewall rules to isolate the routing problem.

My firewall box has 5 interfaces in it but currently only two are involved in the problem. 

eth1: inet addr:192.168.1.224  Bcast:192.168.1.255  Mask:255.255.255.0

eth3: inet addr:192.168.202.1  Bcast:192.168.202.255  Mask:255.255.255.0

eth1 is connected to a switch that is connected to a router.  The router is 192.168.1.1 and is the internet gateway.

eth3 is connected to a different switch.

I have another Centos box that is connected to the switch shared with eth3.  It’s interface is:

eth3: inet addr:192.168.202.10  Bcast:192.168.202.255  Mask:255.255.255.0

I want to provide internet connectivity to this 2^nd machine routed through the firewall.  Currently, I can reach two machines on the 192.168.1.0/24 network (.5 and .3) but I can’t reach the router (.1) or anything outside.

I’ll paste the routing tables from both machines below.  Thanks in advance for your help.

---Marc

Firewall routing tables:

Kernel IP routing table

Destination     Gateway         Genmask         Flags Metric Ref    Use Iface

10.0.0.0        0.0.0.0         255.255.255.254 U     0      0        0 eth4

192.168.1.0     0.0.0.0         255.255.255.0   U     0      0        0 eth1

192.168.202.0   0.0.0.0         255.255.255.0   U     0      0        0 eth3

169.254.0.0     0.0.0.0         255.255.0.0     U     0      0        0 eth4

0.0.0.0         192.168.1.1     0.0.0.0         UG    0      0        0 eth1

192.168.202.10 routing table:

Kernel IP routing table

Destination     Gateway         Genmask         Flags Metric Ref    Use Iface

192.168.202.0   0.0.0.0         255.255.255.0   U     0      0        0 eth1

10.1.16.0       0.0.0.0         255.255.240.0   U     0      0        0 eth0

169.254.0.0     0.0.0.0         255.255.0.0     U     0      0        0 eth0

0.0.0.0         192.168.202.1   0.0.0.0         UG    0      0        0 eth1