Re: [dtn-users] A problem with dtntunnel

["Zoller, David A. (MSFC-EO60)[HOSC SERVICES CONTRACT]" <[e-mail]>]

Hi Sergey,
On RHEL 5.7, I am running dtn-2.9.0 plus modifications that should not impact the behavior of dtntunnel.
I just ran your test without the iptables redirect and I see the same behavior.
I believe that the sender exits if you go directly from nc to nc because the receiver exits when it gets an end of file.
You can add a "-w 1" option to the sender nc so that it will timeout and exit after stdin is idle for 1 second.
Best regards,
DZ

David Zoller
COLSA Corporation
HOSC / C107
*Office: [phone]
*EMail: [e-mail]<mailto:[e-mail]>

From: [e-mail] [mailto:[e-mail]] On Behalf Of [e-mail]
Sent: Tuesday, December 04, 2012 11:13 AM
To: [e-mail]
Subject: [dtn-users] A problem with dtntunnel

Hello all!

I am using dtn-2.9.0 on a RHEL 6 based Linux distro and I am having a problem when using netcat (nc) with dtntunnel.
On the sender node I run "cat /etc/passwd | nc receiver_ip". On the receiver node I run "nc -l 9999". With the help
of Iptables port 9999 gets redirected to the port 19999, which is listened by dtntunnel.

The file /etc/passwd is successfully delivered to the receiver and is shown on the screen. After this the receiving nc exists.
No problem here. However, nc on the sender node doesn't exit after it sends the file. It continues to run forever. When I
run nc in the opposite direction, I get the same problem - the sending nc doesn't exit.

My configuration on both nodes is symmetric:
iptables -t nat -A OUTPUT -d $REMOTE_HOST -p tcp --dport 9999 -j DNAT --to $LOCAL_HOST:19999
dtntunnel -T $LOCAL_HOST:19999:$REMOTE_HOST:9999 $REMOTE_NODE/dtntunnel/nc -d
dtntunnel -L --local-eid $LOCAL_NODE/dtntunnel/nc -d

dtnping works ok in both directions.

Please give me any advice.

With best regards,
Sergey Sireskin