Hi!
I have an unsusal problem. I can ping a internet server from my server (tty) and from the internal network connected to this server, but from the server i cannot traceroute to the same server, although I can do this from any computer inside the internal LAN. Can anyone help me? Because of yhis I can't forward important mail...

PS I am runnig the server with Mandrake 7.1 and Kernel 2.4.2, the internal LAN runs WIndows (several versions)

First i don't see what traceroute have to do with email!!!

Traceroute or related icmp ports may be blocked either by your firewall or by the server you are trying to reach.

I has something to with email, but I don't know what! I can ping that server, but I cannot use telnet 25 for example, so thats why I thought it has something with the fact I can't traceroute.

the fact that you can not traceroute has to do with either your firewall or is a routing issue look at the trace find out where it is stopping usually it is the node after that, that is having the problem. as far as using telnet 25, you need to open port 25 for telnet access if your error says connection refused then that port is not available

Port 25 is open as I can establish a connection with that server, but only within the internal lan, but not from the server that masqaradates the IPs for that LAN

So lets me get this straight.

1.
You can ping , but not trace route.
Your isp may block traceroute packets , mine does. I can ping but Tracert usually dies.
No big deal there.
2.
You can't fwd mail? What do you mean??? Can't send at all?? Is this a new problem? Did it ever work? What changed??

3.Are you running IP masq??

I think what everyone is trying to say Christian is that we need a good detailed description of your network and the problem. :)

Ok.

I'm using a Linux Mandrake 7.1 Kernel 2.4.2 server with 3 Network Cards. One is the main card which I'm using for the international traffic, Interbet IP. The second one is for the internal LAN, local IP. The third one routes the internet to a second server, which is not mine, internet IP. Here is some output of what I mean is not working:

1. ping to that server:
[root@main /root]# ping 193.230.161.230
PING 193.230.161.230 (193.230.161.230): 56 data bytes
64 bytes from 193.230.161.230: icmp_seq=0 ttl=244 time=61.1 ms
64 bytes from 193.230.161.230: icmp_seq=1 ttl=244 time=66.5 ms
64 bytes from 193.230.161.230: icmp_seq=2 ttl=244 time=55.0 ms

--- 193.230.161.230 ping statistics ---
3 packets transmitted, 3 packets received, 0% packet loss
round-trip min/avg/max = 55.0/60.8/66.5 ms
[root@main /root]#

Here is the telnet 25 output:

[root@main /root]# telnet 193.230.161.230 25
Trying 193.230.161.230...
telnet: Unable to connect to remote host: Connection timed out
[root@main /root]#

traceroute to that server, from the linx server:
[root@main /root]# traceroute 193.230.161.230 -n
traceroute to 193.230.161.230 (193.230.161.230), 30 hops max, 38 byte packets
1 193.226.175.241 3.108 ms 2.301 ms 2.354 ms
2 193.226.175.225 12.137 ms 6.995 ms 14.915 ms
3 194.153.225.254 8.578 ms 7.619 ms 26.635 ms
4 193.226.130.25 8.959 ms 8.946 ms 8.972 ms
5 193.226.190.49 31.403 ms 14.557 ms 13.106 ms
6 193.226.131.226 67.496 ms 14.848 ms 13.298 ms
7 134.222.224.41 32.270 ms 60.074 ms 41.422 ms
8 134.222.249.150 89.460 ms 33.241 ms 32.949 ms
9 213.174.68.109 43.795 ms 33.721 ms 46.869 ms
10 195.158.245.242 93.057 ms 265.314 ms 193.217 ms
11 * * *
12 * * *

[root@main /root]#

I've stopped it at hop 12.

The same thing from a PC on the internal LAN:
C:\>tracert 193.230.161.230 -d

Tracing route to [193.230.161.230]
over a maximum of 30 hops:

1

As you can see, it worked.

I was using forwarding email to that server, but since I did switch ti this new one, I can't do it anymore. The old one was a Slackware 2.0.35 linux box.

Is it detailed enough? I hope anyone know what this is about.
Ps I am using iptables to masquerade the IP's.

Ok.

I'm using a Linux Mandrake 7.1 Kernel 2.4.2 server with 3 Network Cards. One is the main card which I'm using for the international traffic, Interbet IP. The second one is for the internal LAN, local IP. The third one routes the internet to a second server, which is not mine, internet IP. Here is some output of what I mean is not working:

1. ping to that server:
[root@main /root]# ping 193.230.161.230
PING 193.230.161.230 (193.230.161.230): 56 data bytes
64 bytes from 193.230.161.230: icmp_seq=0 ttl=244 time=61.1 ms
64 bytes from 193.230.161.230: icmp_seq=1 ttl=244 time=66.5 ms
64 bytes from 193.230.161.230: icmp_seq=2 ttl=244 time=55.0 ms

--- 193.230.161.230 ping statistics ---
3 packets transmitted, 3 packets received, 0% packet loss
round-trip min/avg/max = 55.0/60.8/66.5 ms
[root@main /root]#

Here is the telnet 25 output:

[root@main /root]# telnet 193.230.161.230 25
Trying 193.230.161.230...
telnet: Unable to connect to remote host: Connection timed out
[root@main /root]#

traceroute to that server, from the linx server:
[root@main /root]# traceroute 193.230.161.230 -n
traceroute to 193.230.161.230 (193.230.161.230), 30 hops max, 38 byte packets
1 193.226.175.241 3.108 ms 2.301 ms 2.354 ms
2 193.226.175.225 12.137 ms 6.995 ms 14.915 ms
3 194.153.225.254 8.578 ms 7.619 ms 26.635 ms
4 193.226.130.25 8.959 ms 8.946 ms 8.972 ms
5 193.226.190.49 31.403 ms 14.557 ms 13.106 ms
6 193.226.131.226 67.496 ms 14.848 ms 13.298 ms
7 134.222.224.41 32.270 ms 60.074 ms 41.422 ms
8 134.222.249.150 89.460 ms 33.241 ms 32.949 ms
9 213.174.68.109 43.795 ms 33.721 ms 46.869 ms
10 195.158.245.242 93.057 ms 265.314 ms 193.217 ms
11 * * *
12 * * *

[root@main /root]#

I've stopped it at hop 12.

The same thing from a PC on the internal LAN:

C:\>tracert 193.230.161.230 -d

Tracing route to [193.230.161.230]
over a maximum of 30 hops:

1

As you can see, it worked.

I was using forwarding email to that server, but since I did switch ti this new one, I can't do it anymore. The old one was a Slackware 2.0.35 linux box.

Is it detailed enough? I hope anyone know what this is about.
Ps I am using iptables to masquerade the IP's.

Sorry for that double-post, but I didn't notice that the local LAN traceroute wasn't paste correctly; I can't paste it, it's a f... Windows problem...

I tested the IP 193.230.161.230 from my mail server and it work. May be their mail server (software) was down, but not the computer itself. Or maybe they decided to block smtp trafic comming from your network.

IMHO their address sound like a spamming site!!!

I also tested traceroute and it's look like requests are not forwarded by their router. Several routers or firewall are configured to drop ping and/or traceroute.