this means that all traffic to the 172.16.0.0/16 network goes through eth1.
Now with:
route add -net 172.16.0.0 gw 172.16.1.3
you tell that all traffic to the net 172.16.0.0/16 must go to gateway 172.16.1.3.
Both can not be true at the same time. Moreover how can the gateway 172.16.1.3 be reached when traffic to it (being inside 172.16.0.0/16) should go to 172.16.1.3 (sort of enternal loop there).
Please try to explain how your network looks like on the eth1 side. I get the impression that it is something like:
yoursystem:eth1:172.16.1.9 - LAN172.16.0.0/16 - 172.16.1.3:gateway:172.16.?.? - LAN172.16.0.0/16
As said, this can not function. Please provide more information.
And you say you can not ping. But I love it to see what happens, and not to be told what you think that happens. So please copy and past your ping trial in the same way that you gave us the output of netstat.
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
87.*.*.* * 255.255.255.240 U 0 0 0 eth0
172.16.0.0 plutone.sede.ig 255.255.0.0 UG 0 0 0 eth1
link-local * 255.255.0.0 U 0 0 0 eth0
loopback * 255.0.0.0 U 0 0 0 lo
default 87.*.*.* 0.0.0.0 UG 0 0 0 eth0
172.16.1.3 is the gw for the internal lan (is an isa server)
PING 172.16.1.3 (172.16.1.3) 56(84) bytes of data.
64 bytes from 172.16.1.3: icmp_seq=1 ttl=128 time=0.499 ms
64 bytes from 172.16.1.3: icmp_seq=2 ttl=128 time=0.164 ms
64 bytes from 172.16.1.3: icmp_seq=3 ttl=128 time=0.210 ms
isa_server 2 eth 1 public 87...* 1 private 172.16.1.3 (the gateway)
switch->linux machine 1 eth public 1 private (i can ping only the gw)not working
I am very sorry, but This is not a picture that I understand. Can we give consistent names to the systems that hold longer then half an hour? I called the system your are all the time talking about **yoursystem. **Now you talk about linux system. Is that the same? Does it look like
Please complete this and fill in for every <-> which LAN/network it is by giving the network specification (like 172.16.0.0/16, etc.)
Did you understand what I said about linux_system allready being connected to the 172.16.0.0.16 network and you wanting it to connect to the 172.16.0.0/16 network through 172.16.1.3, which is impossible?
Please try to give as much information as possible and not as less as possible. I can not look to your setup from here, nor in your head.
This can not be true. You made a mess of it. You can not have two default routes. That denies. what the name default means. Your picture is still bogus to me, partly becausr it is difficult to make such pictures using the means we have (a real drawing using some drawing software would be better) and partly because (imho) you do not realy understand what a network is and how traffic is routed.
But as you say it is solved, you will most probably not be interested in my objections. Wishing you all the best with your network.