Re: Greater than 1371 Bytes Output Hangs Session

Bob Simon <bsimon@xxxxxxxxxxx> writes:

On 5 Jul 2006 02:11:34 GMT, Unruh <unruh-spam@xxxxxxxxxxxxxx> wrote:

Bob Simon <bsimon@xxxxxxxxxxx> writes:

From home, I use putty to ssh into a server at work running Red Hat
Linux release 7.2. Commands that display a small amount of output

Yee gads, that is an ancient version. Perhaps you should get the people at
work to upgrade.

Thank you. If I can't fix this problem in the next day or two, I'll
download a newer version, slick the drive, and reinstall linux.

work fine but if I send more than a certain amount to the screen, the
session hangs. The system does not respond to ctrl-c or ctrl-d but I
am able to duplicate the session and re-login. ifdown eth0 followed
by ifup eth0 from the new session does not fix the problem, but I am
able to kill the hung session and continue working until I send too
much output to the screen. When I use putty to log into this server
from a computer on the "inside" network, this problem does not occur.

You do not say how you connect. Is it by a modem or by a network or by an
ADSL connection?

I connect via cable modem at my house. Connectivity to work has been
very stable over the past couple of years except for the two or three
times when I got a new IP address at home. Then, of course, I have to
update my work firewall locally.

I assume you mean "ifdown eth0" on the Redhat machine. However your
comments make no sense, since if you really ran ifdown on the ethernet line
you are connecting with you would no longer have a connection to run ifup
on. Ie you would be disconnected and dead. So something is going on that
you are not telling us.

Yes, I realized that running those commands from home would be like
sawing off the tree limb that I'm sitting on. So I wrote a two line
script that I run with the following two commands:
ifdown eth0
ifup eth0

By experimenting with various file sizes, I determined that I can
repeatedly and successfully cat a file containing 1371 characters.
When I try to cat a file with 1372 characters, nothing is displayed
and the session does not respond to standard input. This should be a
pretty good clue.

What kind of file? Text? Binary?
It sounds to me like a putty problem. What happens if you log on with a
Linux machine from home?

Text. I created the file by "tail -n 15 /var/log/messages > file1".
I initially determined that I could successfully cat 15 lines of log
output but not 16. As I learned later, this varies somewhat depending
on the content of the log file.

So other than loading an updated version of Linux, do you have any
suggestions for me to try?

Nope. But I would run tcpdump on the linux machine while downloading the
1372 file, and the equivalent on the local Windows machine ( no idea what
tools on Windows allows you to sniff the ethernet). Lets see if packets are
leaving the remote and arriving at the local machine. It might also be
someothing that your cable ISP is doing. Do you have a real IP at home or
is your ISP NATing you ( eg do youhave a 192.168.x.x of 10.x.x.x Ip address
at home?)



--
Bob Simon
Please remove Xs from domain for direct replies.
.

Relevant Pages