Telnet session hangs, when I open vi or output is large

[Ashly A K]

hi,

We have a HP UX box. When i can connect to it using putty, from Windows. But, when i start vi or any command, with large put put(like tail, cat etc) the session hangs. At the same time, in some of the Windows boxes, it is working with out any issues! I compared the LAN card settings, putty settings etc in the client, all are same.

Could any one please help me to fix this ? I am totally lost!!!

[Oviwan]

hy

have you the same putty version and have you enabled the session logging in putty?

Regards

[Sharma Sanjeev]

Hi

Try this version

[Ashly A K]

Yes, putty versions are same.

[Ashly A K]

Hi Sanjay,

Tried the attached, but issue remains.

[Anshumali]

Putty settings are same, server is same, file is same, but the behavior is reproducible only from one Windows box!!
Afraid to say, the bottleneck is windows, reinstalling might fix issue. Use your due diligence. :)

[Ashly A K]

hi,

Not one windows boxes- out of 20 windows boxes, we have issues with most of them. compared the patches, versions etc..etc.. with all the boxes, all are same !!!

[Masud Parvez]

If in between windows servers and HPUX box there is firewall then try to avoid firewall and test it.

[Ashly A K]

Hi,

No firewalls!!!

More over, we are able to connect to the HP UX box, and able to execute commands. If the command output is large, the session hangs.


For example, if i say "cat abcd", and the abcd is small, it works. If the file abcd is large, the session hangs, in some of the systems.

[Masud Parvez]

Which one you are using ssh or telnet when using putty?

[Sharma Sanjeev]

Hi Ashly

Please try this

open putty session

window > Line to Scrollback > make it 200000

Regards
Sanjeev

[Deepak Kr]

Hi Ashly,

Try this also:

Open a telnet session to hp-ux box

run following

stty ixoff
/bin/X11/resize

cat file_name_you_want_to_open...

[Torsten.]

I would use

"pathping"

from the window box to ensure or check connectivity first.

Just type

"pathping"

for more options.

[Ashly A K]

Another possible suspect is, the HP UX and Windows boxes are in different sub-nets. But, some of the Win boxes in this sub net works and some doesn't works.

How can i narrow down, whether this is a network issue or a server issue or a client issue ?

I am totally lost!!

[Anshumali]

We can try following 2 things:

1. Re-IP the windows which is not working with the IP which is working.
2. Capture Ethreal at time of pasting and compare.

1st can be tried immediately.

Anshu

[Ph. LAQUERRIERE]

Could you see a lan configuration between your HP box and a switch, because in some case if your switch conf is in autoneg and your HP box too, you can have the problem.
you must force full duplex in all component, or in HP box.

Regards.

[Anshumali]

I wouldn't suggest touching HP box......... :)

[Jov]

Hi,

Repeat the same functions that causes the error, but without logging to eliminate this factor.


Jov

[Mark Ellzey]

Hi,

Check the usage of /tmp on the HP box. If you are trying to vi a large file, vi uses /tmp (or /var/tmp, I don't remember which) to create a temp file of what you are editing. If /tmp if full, or nearly so, vi will bomb. Ususally, though, it will tell you that it does't have enough space to open the file.

Just my 2cts.
Mark

[Anshumali]

Mark,

he mentioned, "At the same time, in some of the Windows boxes, it is working with out any issues!"

In this case, i dont see any thing on hp-ux as issue is not always reproducible from all Win boxes... :-)

Cheers!

[Trevor Roddam_1 · Accepted solution]

Hi.

This may lead to nothing but I have seen this when the server and the switch have mismatched Duplex on the NIC.

Find out what the switch is set to (Auto, 1000FD, 1000HD etc) and then use landiag to look at the duplex setting of the NIC.
lanscan will show you which card number to reference.

It will probably be set to the opposite of the switch IE half duplex instead of full.....
It will probably be a CISCO switch too.

Reset both to the same and all is OK...

Trevor.

[Ashly A K]

Hey,

it might be a network issue. we are planning to change from half duplex to full.

mean while, any other ideas, MOST Welcome

[Ralph Grothe]

>More over, we are able to connect to the HP UX >box, and able to execute commands. If the >command output is large, the session hangs.

I'm not sure, but this sounds as if the path MTU discovery between Putty client and HP-UX server is impaired.
Could it be that you have any blackhole routers along the route (viz. those which aren't allowed to return ICMP "fragmentation needed" packets)?
Some network device admins block all (even legitimate) ICMP traffic).
I'm not sure about the Windows ping command,
but I think it also allows for giving the packet size (try WINkey+r => cmd to get a DOS shell and enter "ping /h" for valid options).
Then you could try to send echo request packets of increasing size (provided these aren't filtered, and the HP-UX server is allowed to respond), and check from when you encounter packet loss.
But I suppose in order to reduce the MTU of your windows box you need to tamper with some registry setting, of which I am afraid I am clueless.

[Ashly A K]

Thank you All!!! It was the issue with MTU settings in the client PCs...

Thanks a TON for the inputs!!!