[Qemu-devel] user-net -redir working?

[Richard Neill <rn214@hermes.cam.ac.uk>]

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Re: User-net not working:

> Disabling the Nagle algorithm (i.e., enabling TCP_NODELAY) or typing a
> lot of garbage just to fill the buffer with enough data can help,
> also.
> 
> And IIRC, netcat has a UDP mode as well. I see no reason for this to
> happen, but is there any chance it's using UDP by default, and you're
> only redirecting TCP?
> 
> Good luck!

Thanks for your message.

I think that -redir really is broken: I've also been unsuccessful in 
trying to make it work using an FTP server on a Windows guest, and using 
the SSH server on a knoppix guest. Has anyone here ever had success with 
it? It also fails on hosts with 2 different versions of Mandrake.

Anyway, I've taken your suggestion, and run both ends with ethereal. 
Here's what I did:


HOST (Linux);
   qemu -cdrom /dev/cdrom -boot d -user-net -redir tcp:2200::22

GUEST (Knoppix):
   Boot up, then start sshd. Verify that I can indeed do ssh
   root@localhost, and that PermitRootLogin is yes in sshd_config.

    Then, start ethereal (on the "any" interface)


HOST:
   Start ethereal (on the "any" interface")
   ssh -p 2200 root@localhost

  At this point, ssh just stalls. It's obviously waiting for something,
  but not known what. I get no output at all from it.


End of experiment.

ETHEREAL on HOST is showing a series of empty packets:

    SYN
    SYN
    ACK
    FIN
    ACK
    FIN
    ACK
    [repeats]


  ETHEREAL on GUEST is showing a series of empty packets, all of which 
are SYN.

I have no problem in making an outgoing connection from the GUEST to the 
  HOST.


I'm attaching both log files - they are only 2.5 kB

Any ideas? Has anyone succesfully used the user-net -redir option?


Richard

[-- Attachment #2: ethereal.guest.log --]
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[-- Attachment #3: ethereal.host.log --]
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