Help!!! Strange Network Problem ???

Help!!! Strange Network Problem ???

Post by Izauddi » Mon, 30 Jun 1997 04:00:00

Hi guys,

I have this strange problem on my network. I using linux redhat 4.1
with a ppp connection to the Internet (ISP) as my gateway box. I running
two web server in my network, one is the linux box the other one is
running on SCO Unix. Previously the connection work without a problem,
but then strange thing happen.  

The problem is that people outside of my network cannot access the
both the web server, but internally I can access the server fine.
The config file for both the web server allow all to access the servers.
Said that people outside trying to connect to my home page, the message
at the bottom of the browsers will say that it connecting to the web
server, and then transferring data. But it will time out with an error
messages saying that the server is not responding.

At the server side when I do netstat -c when the people trying to
connect I see this :

tcp 0 4767 <local address> <foreign address> FIN_WAIT1

At the web server log I see this :

<outside address> - - [date:time -0800] "GET / HTTP/1.0" 200 4766

I can go out to the Internet fine, without any problem, but cannot ping
to my network from outside, can only ping the serial ppp connection
FTP & telnet also giving the same problem, I can telnet and ftp from
outside to my gateway server through the server ppp ip address but not
the internal address.
My gateway local ppp ip address is and the gateway
ethernet ip
address is and my network number is with a
of and my static route as follow :-

Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS dow  irtt
Iface UH     1500 0          0
eth0:0 UH     1500 0          0
ppp0 U      1500 0          0
eth0     UG     1500 0          0
ppp0       U      3584 0          0
lo         UG     1500 0          0

What could have gone wrong ?

Thanks for any info.



1. HELP: a strange network problem


  I have a mysterious network problem. I have a Sun (with SunOS) and
several Digital (OSF1, ver. 4.2) workstations. The NIS service is
installed, the DNS is not (so far).

  When I try to run 'rlogin' or 'rsh' on some (not all) computers it's
OK so far I use their symbolic name for reference (like 'rlogin comp1').
However, if I try to use their IP address, I get a message:
"XXX.XX.XX.XX: unknown address. If I use their IP addresses for
reference in 'telnet' or 'ping' command it works OK.

  As far as I know every symbolic alias is eventually converted into an
IP address, so what's the hell ?

  Please, respond by e-mail!

                        Thank you.

Sergey Rosenblum

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