To telnet or to netcat... that's the question

NOSpaze nospaze at gmail.com
Sat Sep 1 03:01:23 UTC 2012


On Fri, 2012-08-31 at 14:14 +0100, Bryn M. Reeves wrote:
> On 08/31/2012 01:41 PM, NOSpaze wrote:
> > But if I use nc and do...
> > 
> >         # nc 127.0.0.1 5038 << EOF
> >         > Action: Login
> >         > ActionID: 1
> >         > Username: youwanna
> >         > Secret: uwanna
> >         > 
> >         > EOF
> >         Asterisk Call Manager/1.0
> 
> Does the behaviour differ if you type or paste the lines in and then hit
> Ctrl-D (or your keybinding for EOF) rather than use a shell here document?

No. Even when I slowly wrote it.

> I think this might cause nc to send one big packet with all the lines
> which might not be what asterisk expects. I'd also expect telnet to turn
> of nagling on the socket (so data is sent immediately rather than
> buffering). I think nc doesn't do that although it does provide a
> configurable send/receive delay interval (-i).

I used big delays. No difference.

> Failing that I would try a tethereal/tcpdump to see what's different in
> the data going over the wire.

Already tried, tcpdump -X. The process is completely different (telnet
is interactive, nc don't), and I dont' get which is the precise problem.
I've already used nc with asterisk, and worked fine. Maybe is my
asterisk version...

Thanks!



More information about the users mailing list