RE: [lwip-users] Remote tcp connection with TAPIF interface

[jean-louis . gilbert]

Hello Andreas,

> Did you set /proc/sys/net/ipv4/ip-forward to 1 ?
Yes i set this value on both sides.

> What IP / Gateway's do you use?
For me the "IP/Gateway" is set in the source code of each of the Hosts A and
B. (This correspond to what you called underneath: "lw-gw Host xxx: yyyy".
This value corresponds to the Tap0 interface.

In fact my Configuration is:

linux 2.4.18 with lwip-0.7.1 on both sides:

192.168.0.

Host A: 3 (bridge br0)
lwip-gw Host A: 4
lwip-ip Host A: 5

Host B: 6 (bridge br1)
lwip-gw Host B: 1
lwip-ip Host B: 2 

Besides:
1. I set on Host A the HwAddress of the bridge <-->IPAddress of Application
("lwip-ip") of Host B (i.e. ethernet board) in the linux ARP table:
        "arp -s 192.168.0.2 HwAddress-br1"

1. I set on Host B the HwAddress of the bridge <-->IPAddress of Application
("lwip-ip") of Host A (i.e. ethernet board) in the linux ARP table:
        "arp -s 192.168.0.5 HwAddress-br0"

>I work with only one bridge on one linux host, but TCP works realy fine.
(The other side is an windows Host.)

Do you work with lwip on the windows host ? In fact, i try to connect to
Host B without using lwip on host A (i use telnet), all is OK. However,
when, on host A i try to use a simple socket application ("socket" +
"connect") compiled with lw-ip, and in this case, the "connect" function
returns an error.

Now, i'm trying to see the exact IP and TCP header created by Lw-IP when it
tries to "connect" and compare to those send by telnet (linux
application)...

Thanks fo your help..

Jean-Louis


-----Message d'origine-----
De: Andreas Becker [mailto:address@hidden
Date: jeudi 2 septembre 2004 17:07
À: address@hidden
Objet: RE: [lwip-users] Remote tcp connection with TAPIF interface


Hello Jean-louis,


> However, for a unicast tcp connection, I notice that IP packets manage to
> exit the client side ("connect" fucntion), they reach the remote Bridge
> (br1) on the "server" side, but once they are on this machine, the packets
> are not "forwarded" to TAP0 interface.... (tcpdump).

( without mailinglist if something helps please put it to the list.)

Did you set /proc/sys/net/ipv4/ip-forward to 1 ?

What IP / Gateway's do you use?

My Configuration:

192.168.0.
Host A: 1
lwip-gw Host A: 10
lwip-ip Host A: 11

Host B: 2
lwip-gw Host B: 20
lwip-ip Host B: 21

You need an IP for your TAP0 device, this is the gateway IP.

I work with only one bridge on one linux host, but TCP works realy fine.
(The other side is an windows Host.)


-- 
Dipl.-Ing.(FH) Andreas Becker
Entwicklung

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