Help !! I have Redhat Fadora. I have setup ip_forward on nic card. Ip_forward is working fine when I ping from one port to another. However I can not send any TCP or UDP packet across. I have capture error massage using tcpdump see below for detail. I do not understand error massage.

Here is my overall configuration IP address.

Linux Eth1 192.168.5.1 --> PC1 (192.168.5.2 gw 192.168.5.1)
Linux Eth2 192.168.1.1--> PC 2 (192.168.1.2 gw 192.168.1.1)

Using tcpdump
16:20:20.330365 IP 192.168.5.1 > 192.168.5.2: ICMP host 192.168.1.2 unreachable - admin prohibited, length 56

Kernel IP routing table
Destination Gateway Genmask Flags MSS Window irtt Iface
192.168.5.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth2
169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth2
0.0.0.0 192.168.1.2 0.0.0.0 UG 0 0 0 eth2

I do appreciate any help

Thank you very much.
Jay

looks like you have a local firewall on the box running iptables with a reject for icmp on a --icmp-admin-prohibited function. check system-config-securitylevel on fedora

I was able to flush out all of the policy in iptables. It is working. Thank you so much for your help. You have been so much helpful.

Jay