Bug #672

Reflection, netcat usage error

Added by Lars Hupfeldt Nielsen about 9 years ago. Updated over 8 years ago.

Target version:
Start date:
Due date:
% Done:


Estimated time:
Affected Version:
Affected Architecture:


Trying to telnet to a NATted server gives the following error:

xx@xx:~$ telnet xxx.xx 2201
Trying xx.xx.xx.xx...
Connected to xxx.xx.
Escape character is '^]'.
usage: nc [-46DdEhklnrStUuvz] [-e policy] [-I length] [-i interval] [-O length]
[-P proxy_username] [-p source_port] [-s source_ip_address] [-T ToS]
[-V fib] [-w timeout] [-X proxy_protocol]
[-x proxy_address[:port]] [hostname] [port]

SSH to the same server is working. NAT and rules for SSH and my other service on port 2201 is setup exactly the same, except for the port numbers and usage of aliases for the other service.

Associated revisions

Revision 0532e54d (diff)
Added by Erik Fonnesbeck over 8 years ago

Rework handling of ports for reflection on port forwards to work properly with port aliases. Ticket #672


#1 Updated by Chris Buechler about 9 years ago

  • Target version set to 2.0

#2 Updated by Erik Fonnesbeck about 9 years ago

Do you have multiple ports in the same alias? Specifically on the one that is failing.

#3 Updated by Lars Hupfeldt Nielsen about 9 years ago

No, just a single port (2201).

#4 Updated by Lars Hupfeldt Nielsen about 9 years ago

I have other aliases with multiple ports, none of them are overlapping. Reflection is not working for other services either, only for ssh, it seems. Is ssh given special treatment? Could it be a privileged vs non privileged port thing?

#5 Updated by Erik Fonnesbeck about 9 years ago

Aliases with multiple ports do not currently work with Reflection, though there actually isn't really any reason it couldn't work.

#6 Updated by Ermal Luçi almost 9 years ago

  • Status changed from New to Feedback

It should not error out, but it will skip mostly aliases with multiple ports!

#7 Updated by Ermal Luçi over 8 years ago

  • Status changed from Feedback to Resolved

This avoids errors and does the right thing now.

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