Debian Bug report logs - #614291
Unable to establish qemu+ssh connection

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Message #5 received at submit@bugs.debian.org (full text, mbox, reply):

From: Michael Biebl <biebl@debian.org>

To: Debian Bug Tracking System <submit@bugs.debian.org>

Subject: Unable to establish qemu+ssh connection

Date: Sun, 20 Feb 2011 21:52:11 +0100

Package: virt-manager
Version: 0.8.6-2
Severity: important

Hi,

I have successfully used virt-manager to conntect a libvirt managed KVM
server via SSH in the past.

I'm not sure anymore which upgrade caused the failure, but for the
previously working qemu+ssh://root@host connection I now get the
following error message:

Unable to open a connection to the libvirt management daemon.

Libvirt URI is: qemu+ssh://root@foo/system

Verify that:
 - The 'libvirtd' daemon has been started

server closed connection: nc: invalid option -- 'U'
nc -h for help


Traceback (most recent call last):
  File "/usr/share/virt-manager/virtManager/connection.py", line 1022, in _try_open
    None], flags)
  File "/usr/lib/python2.6/dist-packages/libvirt.py", line 107, in openAuth
    if ret is None:raise libvirtError('virConnectOpenAuth() failed')
libvirtError: server closed connection: nc: invalid option -- 'U'
nc -h for help



The client system is Debian unstable, the KVM server runs an up-to-date
Debian squeeze.

Michael

-- System Information:
Debian Release: wheezy/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (200, 'experimental')
Architecture: i386 (i686)

Kernel: Linux 2.6.37-1-686 (SMP w/1 CPU core)
Locale: LANG=de_DE.utf8, LC_CTYPE=de_DE.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages virt-manager depends on:
ii  gconf2                  2.28.1-6         GNOME configuration database syste
ii  librsvg2-common         2.26.3-1         SAX-based renderer library for SVG
ii  python                  2.6.6-3+squeeze5 interactive high-level object-orie
ii  python-dbus             0.83.1-1         simple interprocess messaging syst
ii  python-glade2           2.17.0-4         GTK+ bindings: Glade support
ii  python-gnome2           2.28.1-1         Python bindings for the GNOME desk
ii  python-gtk-vnc          0.4.1-4          A VNC viewer widget for GTK+ (Pyth
ii  python-gtk2             2.17.0-4         Python bindings for the GTK+ widge
ii  python-ipy              1:0.72-1         Python module for handling IPv4 an
ii  python-libvirt          0.8.7-3          libvirt Python bindings
ii  python-support          1.0.11           automated rebuilding support for P
ii  python-urlgrabber       3.9.1-4          A high-level cross-protocol url-gr
ii  python-vte              1:0.24.3-2       Python bindings for the VTE widget
ii  virtinst                0.500.5-1        Programs to create and clone virtu

Versions of packages virt-manager recommends:
ii  gnome-icon-theme              2.30.3-2   GNOME Desktop icon theme
pn  libvirt-bin                   <none>     (no description available)

Versions of packages virt-manager suggests:
ii  gnome-keyring                 2.30.3-5   GNOME keyring services (daemon and
ii  hal                           0.5.14-5   Hardware Abstraction Layer
ii  python-gnomekeyring           2.30.0-4   Python bindings for the GNOME keyr
pn  ssh-askpass                   <none>     (no description available)
ii  virt-viewer                   0.2.1-1    Displaying the graphical console o

-- no debconf information

Message #10 received at 614291@bugs.debian.org (full text, mbox, reply):

From: Guido Günther <agx@sigxcpu.org>

To: Michael Biebl <biebl@debian.org>, 614291@bugs.debian.org

Subject: Re: [Pkg-libvirt-maintainers] Bug#614291: Unable to establish qemu+ssh connection

Date: Sun, 20 Feb 2011 22:13:33 +0100

On Sun, Feb 20, 2011 at 09:52:11PM +0100, Michael Biebl wrote:
> Package: virt-manager
> Version: 0.8.6-2
> Severity: important
> 
> Hi,
> 
> I have successfully used virt-manager to conntect a libvirt managed KVM
> server via SSH in the past.
> 
> I'm not sure anymore which upgrade caused the failure, but for the
> previously working qemu+ssh://root@host connection I now get the
> following error message:
> 
> Unable to open a connection to the libvirt management daemon.
> 
> Libvirt URI is: qemu+ssh://root@foo/system
> 
> Verify that:
>  - The 'libvirtd' daemon has been started
> 
> server closed connection: nc: invalid option -- 'U'
> nc -h for help
> 
> 
> Traceback (most recent call last):
>   File "/usr/share/virt-manager/virtManager/connection.py", line 1022, in _try_open
>     None], flags)
>   File "/usr/lib/python2.6/dist-packages/libvirt.py", line 107, in openAuth
>     if ret is None:raise libvirtError('virConnectOpenAuth() failed')
> libvirtError: server closed connection: nc: invalid option -- 'U'
> nc -h for help
> 
> 
> 
> The client system is Debian unstable, the KVM server runs an up-to-date
> Debian squeeze.
You're using netcat-openbsd? 
 -- Guido

Message #15 received at 614291@bugs.debian.org (full text, mbox, reply):

From: Michael Biebl <biebl@debian.org>

To: Guido Günther <agx@sigxcpu.org>

Cc: 614291@bugs.debian.org

Subject: Re: [Pkg-libvirt-maintainers] Bug#614291: Unable to establish qemu+ssh connection

Date: Sun, 20 Feb 2011 22:23:24 +0100

[Message part 1 (text/plain, inline)]

Am 20.02.2011 22:13, schrieb Guido Günther:

> You're using netcat-openbsd? 

Server or Client?

-- 
Why is it that all of the instruments seeking intelligent life in the
universe are pointed away from Earth?

[signature.asc (application/pgp-signature, attachment)]

Message #20 received at 614291@bugs.debian.org (full text, mbox, reply):

From: Michael Biebl <biebl@debian.org>

To: Guido Günther <agx@sigxcpu.org>

Cc: 614291@bugs.debian.org

Subject: Re: [Pkg-libvirt-maintainers] Bug#614291: Unable to establish qemu+ssh connection

Date: Sun, 20 Feb 2011 22:28:53 +0100

[Message part 1 (text/plain, inline)]

Am 20.02.2011 22:23, schrieb Michael Biebl:
> Am 20.02.2011 22:13, schrieb Guido Günther:
> 
>> You're using netcat-openbsd? 
> 
> Server or Client?

Nevermind. I just checked the KVM server and netcat-openbsd was not installed.
Installing it solved the problem.
I can't reproduce anymore, why netcat-openbsd was removed when dist-upgrading
from lenny to squeeze.


That said, would it be possible to provide a more meaningful error message in
virt-manager?
I would have never guessed that to be a problem of a missing netcat-openbsd.

Cheers,
Michael


-- 
Why is it that all of the instruments seeking intelligent life in the
universe are pointed away from Earth?

[signature.asc (application/pgp-signature, attachment)]

Message #25 received at 614291@bugs.debian.org (full text, mbox, reply):

From: Luca Capello <luca@pca.it>

To: 614291@bugs.debian.org

Cc: Michael Biebl <biebl@debian.org>

Subject: Re: Bug#614291: [Pkg-libvirt-maintainers] Bug#614291: Unable to establish qemu+ssh connection

Date: Sat, 05 Mar 2011 15:54:02 +0100

[Message part 1 (text/plain, inline)]

found 614291 0.8.4-8
tags 614291 + patch
thanks

Hi there!

NB, this could be considered a duplicate of #453627 ;-)

On Sun, 20 Feb 2011 22:28:53 +0100, Michael Biebl wrote:
> Am 20.02.2011 22:23, schrieb Michael Biebl:
>> Am 20.02.2011 22:13, schrieb Guido Günther:
>> 
>>> You're using netcat-openbsd? 
>> 
>> Server or Client?

Server: netcat-traditional
Client: netcat-openbsd and netcat-traditional, /bin/nc pointing to
        /bin/nc.openbsd (auto priority 50 over 10)

> Nevermind. I just checked the KVM server and netcat-openbsd was not installed.
> Installing it solved the problem.

Here as well, simply installing netcat-openbsd on the server solved the
problem.
     
However, this is because netcat-openbsd has a higher alternative
priority than netcat-traditional, which means that if you manually
manage nc alternative and set it to netcat-traditional, the problem is
still there.  Read below for a possible solution.

> I can't reproduce anymore, why netcat-openbsd was removed when dist-upgrading
> from lenny to squeeze.

I have never had netcat-openbsd on the server and installing libvirt-bin
did not bring it in.

> That said, would it be possible to provide a more meaningful error message in
> virt-manager?
> I would have never guessed that to be a problem of a missing netcat-openbsd.

While I agree, at the same time the error message is quite clear, at
least at the beginning, while at the end, where it asks to check if
libvirtd is running, the message is simply useless.

The bug seems in libvirt-bin (at least 0.8.3-5), not virt-manager, since
setting the nc alternative to netcat-traditional on the client still
lets virt-manager connect to the server.

So, I see two solutions, beside the fact that libvirt-bin should depend
on netcat-openbsd:

1) libvirt-bin calls /bin/nc.openbsd, not elegant, but it avoids any
   problem in an automatic way

2) libvirt-bin still calls /bin/nc, but the need for netcat-openbsd
   should be documented at least in the README.Debian, something like

--8<---------------cut here---------------start------------->8---
--- !home!luca!README.Debian.~1~	2011-03-05 15:47:44.000000000 +0100
+++ /home/luca/README.Debian	2011-03-05 15:51:26.000000000 +0100
@@ -16,6 +16,18 @@
 libvirtd to access xen with unprivileged users and add the users to the
 "libvirt" group (see "Access Control" below).
 
+SSH connections to the server
+=============================
+
+If you want to connect to the libvirt server via SSH, you need to
+install netcat-openbsd on the server and configure the nc alternative
+to use it.  This is done automatically when netcat-openbsd is
+installed if you do not have previously modified the nc alternative.
+Please see the following bug reports for a complete explanation:
+
+  <http://bugs.debian.org/453627>
+  <http://bugs.debian.org/614291>
+
 Debugging
 =========
 Use LIBVIRT_DEBUG=1 to enable libvirt's debugging output, e.g.:
--8<---------------cut here---------------end--------------->8---

Thx, bye,
Gismo / Luca

[Message part 2 (application/pgp-signature, inline)]

Message #34 received at 614291@bugs.debian.org (full text, mbox, reply):

From: Guido Günther <agx@sigxcpu.org>

To: Luca Capello <luca@pca.it>, 614291@bugs.debian.org

Cc: Michael Biebl <biebl@debian.org>

Subject: Re: [Pkg-libvirt-maintainers] Bug#614291: Bug#614291: Unable to establish qemu+ssh connection

Date: Sun, 6 Mar 2011 17:37:47 +0100

Hi,
On Sat, Mar 05, 2011 at 03:54:02PM +0100, Luca Capello wrote:
[..snip..] 
> So, I see two solutions, beside the fact that libvirt-bin should depend
> on netcat-openbsd:

virt-manager invokes netcat on the remote side for console access.

> 
> 1) libvirt-bin calls /bin/nc.openbsd, not elegant, but it avoids any
>    problem in an automatic way

This would break non Debian systems. We could check for nc.openbsd first
and then fall back to nc though (which would mean fixing up
Autodetect-if-the-remote-nc-command-supports-the-q-o.patch) but in that
case it's probably easier to drop the dependency altogether (which is
what upstream plans to do).

> 2) libvirt-bin still calls /bin/nc, but the need for netcat-openbsd
>    should be documented at least in the README.Debian, something like

Applied, thanks. I'll leave the bug open though since improving the
error message is still a good idea.
Cheers,
 -- Guido

Message #39 received at 614291@bugs.debian.org (full text, mbox, reply):

From: Luca Capello <luca@pca.it>

To: Guido Günther <agx@sigxcpu.org>

Cc: 614291@bugs.debian.org, Michael Biebl <biebl@debian.org>

Subject: Re: [Pkg-libvirt-maintainers] Bug#614291: Bug#614291: Unable to establish qemu+ssh connection

Date: Mon, 07 Mar 2011 13:17:16 +0100

[Message part 1 (text/plain, inline)]

Hi there!

On Sun, 06 Mar 2011 17:37:47 +0100, Guido Günther wrote:
> Hi,
> On Sat, Mar 05, 2011 at 03:54:02PM +0100, Luca Capello wrote:
> [..snip..] 
>> So, I see two solutions, beside the fact that libvirt-bin should depend
>> on netcat-openbsd:
>
> virt-manager invokes netcat on the remote side for console access.

Mmm, while I see your point, the only way to assure netcat-openbsd is
installed on the remote side is a dependency in libvirt-bin, given that
virt-manager is not required on the remote side.

>> 1) libvirt-bin calls /bin/nc.openbsd, not elegant, but it avoids any
>>    problem in an automatic way
>
> This would break non Debian systems. We could check for nc.openbsd first
> and then fall back to nc though (which would mean fixing up
> Autodetect-if-the-remote-nc-command-supports-the-q-o.patch) but in that
> case it's probably easier to drop the dependency altogether (which is
> what upstream plans to do).

I am not sure I have completely understood what you wrote:

1) Autodetect-if-the-remote-nc-command-supports-the-q-o.patch was
   introduced because of #573172.  In Debian Both netcat-traditional and
   netcat-openbsd have the -q option, but none of the upstream netcat
   has it [1][2].

2) modifying the patch above is IMHO not a good thing, given that these
   two issues (-q and -U) are completely different, with the latter (-U)
   being common to all versions other than the OpenBSD netcat (#348564).

3) what does "but in that case it's probably easier to drop the
   dependency altogether (which is what upstream plans to do)" mean?
   That -U will not be needed anymore?  In this case, I think that,
   beside fixing the dependencies and documenting this bug, nothing more
   should be done.

[1] the original Hobbit's netcat <http://nc110.sourceforge.net/>
    OpenBSD netcat <http://www.openbsd.org/cgi-bin/cvsweb/src/usr.bin/nc/>
    GNU netcat <http://netcat.sourceforge.net/>
    Nmap ncat <http://nmap.org/ncat/>
[2] netcat-traditional got it in 1999 (1.10-12, #45675) and
    netcat-openbsd with its first upload in 2008 (1.89-1, #461317)

>> 2) libvirt-bin still calls /bin/nc, but the need for netcat-openbsd
>>    should be documented at least in the README.Debian, something like
>
> Applied, thanks. I'll leave the bug open though since improving the
> error message is still a good idea.

Thank you.

Thx, bye,
Gismo / Luca

[Message part 2 (application/pgp-signature, inline)]

Message #44 received at 614291@bugs.debian.org (full text, mbox, reply):

From: Luca Capello <luca@pca.it>

To: 614291@bugs.debian.org

Cc: Guido Günther <agx@debian.org>, Michael Biebl <biebl@debian.org>, Decklin Foster <decklin@debian.org>

Subject: Re: [Pkg-libvirt-maintainers] Bug#614291: Bug#614291: Unable to establish qemu+ssh connection

Date: Tue, 08 Mar 2011 10:41:57 +0100

[Message part 1 (text/plain, inline)]

Hi there!

On Mon, 07 Mar 2011 13:17:16 +0100, Luca Capello wrote:
> On Sun, 06 Mar 2011 17:37:47 +0100, Guido Günther wrote:
>> On Sat, Mar 05, 2011 at 03:54:02PM +0100, Luca Capello wrote:
>> [..snip..] 
>>> So, I see two solutions, beside the fact that libvirt-bin should depend
>>> on netcat-openbsd:
>>
>> virt-manager invokes netcat on the remote side for console access.
>
> Mmm, while I see your point, the only way to assure netcat-openbsd is
> installed on the remote side is a dependency in libvirt-bin, given that
> virt-manager is not required on the remote side.
>
>>> 1) libvirt-bin calls /bin/nc.openbsd, not elegant, but it avoids any
>>>    problem in an automatic way
>>
>> This would break non Debian systems. We could check for nc.openbsd first
>> and then fall back to nc though (which would mean fixing up
>> Autodetect-if-the-remote-nc-command-supports-the-q-o.patch) but in that
>> case it's probably easier to drop the dependency altogether (which is
>> what upstream plans to do).
>
> I am not sure I have completely understood what you wrote:
>
> 1) Autodetect-if-the-remote-nc-command-supports-the-q-o.patch was
>    introduced because of #573172.  In Debian Both netcat-traditional and
>    netcat-openbsd have the -q option, but none of the upstream netcat
>    has it [1][2].

Actually, I found another bug which is even more interesting: #564034.
There, the netcat-openbsd maintainer (cc:ed) announced that he had
restored the original behavior if -q is not given:

--8<---------------cut here---------------start------------->8---
netcat-openbsd (1.89-4) unstable; urgency=low

  * Quit immediately after EOF if -q is not given (i.e. make the default
    equivalent to -q 0). This is the standard upstream behavior and what
    other Linux distributions use. It is different from netcat-traditional,
    but compatibility with other versions of OpenBSD netcat is more
    important. (Closes: #502188)

 -- Decklin Foster <decklin@red-bean.com>  Sun, 18 Apr 2010 20:05:08 -0400
--8<---------------cut here---------------end--------------->8---

So, am I right that we do not need anymore the -q patch if libvirt-bin
and virt-manager depends on netcat-openbsd >= 1.89-4?

Thx, bye,
Gismo / Luca

[Message part 2 (application/pgp-signature, inline)]

Message #49 received at 614291@bugs.debian.org (full text, mbox, reply):

From: Guido Günther <agx@sigxcpu.org>

To: Luca Capello <luca@pca.it>

Cc: 614291@bugs.debian.org, Michael Biebl <biebl@debian.org>, Decklin Foster <decklin@debian.org>

Subject: Re: [Pkg-libvirt-maintainers] Bug#614291: Bug#614291: Unable to establish qemu+ssh connection

Date: Tue, 8 Mar 2011 11:06:34 +0100

On Tue, Mar 08, 2011 at 10:41:57AM +0100, Luca Capello wrote:
> Hi there!
> 
> On Mon, 07 Mar 2011 13:17:16 +0100, Luca Capello wrote:
> > On Sun, 06 Mar 2011 17:37:47 +0100, Guido Günther wrote:
> >> On Sat, Mar 05, 2011 at 03:54:02PM +0100, Luca Capello wrote:
> >> [..snip..] 
> >>> So, I see two solutions, beside the fact that libvirt-bin should depend
> >>> on netcat-openbsd:
> >>
> >> virt-manager invokes netcat on the remote side for console access.
> >
> > Mmm, while I see your point, the only way to assure netcat-openbsd is
> > installed on the remote side is a dependency in libvirt-bin, given that
> > virt-manager is not required on the remote side.
> >
> >>> 1) libvirt-bin calls /bin/nc.openbsd, not elegant, but it avoids any
> >>>    problem in an automatic way
> >>
> >> This would break non Debian systems. We could check for nc.openbsd first
> >> and then fall back to nc though (which would mean fixing up
> >> Autodetect-if-the-remote-nc-command-supports-the-q-o.patch) but in that
> >> case it's probably easier to drop the dependency altogether (which is
> >> what upstream plans to do).
> >
> > I am not sure I have completely understood what you wrote:
> >
> > 1) Autodetect-if-the-remote-nc-command-supports-the-q-o.patch was
> >    introduced because of #573172.  In Debian Both netcat-traditional and
> >    netcat-openbsd have the -q option, but none of the upstream netcat
> >    has it [1][2].
> 
> Actually, I found another bug which is even more interesting: #564034.
> There, the netcat-openbsd maintainer (cc:ed) announced that he had
> restored the original behavior if -q is not given:
> 
> --8<---------------cut here---------------start------------->8---
> netcat-openbsd (1.89-4) unstable; urgency=low
> 
>   * Quit immediately after EOF if -q is not given (i.e. make the default
>     equivalent to -q 0). This is the standard upstream behavior and what
>     other Linux distributions use. It is different from netcat-traditional,
>     but compatibility with other versions of OpenBSD netcat is more
>     important. (Closes: #502188)
> 
>  -- Decklin Foster <decklin@red-bean.com>  Sun, 18 Apr 2010 20:05:08 -0400
> --8<---------------cut here---------------end--------------->8---
> 
> So, am I right that we do not need anymore the -q patch if libvirt-bin
> and virt-manager depends on netcat-openbsd >= 1.89-4?

No, we still need to support this for interoperability with other Linux
distributions. There are lots of people using virt-manager on Debian to
manage remote RedHat, SuSE, whatnot.
Cheers,
 -- Guido

Message #54 received at 614291@bugs.debian.org (full text, mbox, reply):

From: Guido Günther <agx@sigxcpu.org>

To: Luca Capello <luca@pca.it>

Cc: 614291@bugs.debian.org, Michael Biebl <biebl@debian.org>, Decklin Foster <decklin@debian.org>

Subject: Re: [Pkg-libvirt-maintainers] Bug#614291: Bug#614291: Unable to establish qemu+ssh connection

Date: Tue, 8 Mar 2011 11:08:09 +0100

On Tue, Mar 08, 2011 at 11:06:34AM +0100, Guido Günther wrote:
> On Tue, Mar 08, 2011 at 10:41:57AM +0100, Luca Capello wrote:
> > Hi there!
> > 
> > On Mon, 07 Mar 2011 13:17:16 +0100, Luca Capello wrote:
> > > On Sun, 06 Mar 2011 17:37:47 +0100, Guido Günther wrote:
> > >> On Sat, Mar 05, 2011 at 03:54:02PM +0100, Luca Capello wrote:
> > >> [..snip..] 
> > >>> So, I see two solutions, beside the fact that libvirt-bin should depend
> > >>> on netcat-openbsd:
> > >>
> > >> virt-manager invokes netcat on the remote side for console access.
> > >
> > > Mmm, while I see your point, the only way to assure netcat-openbsd is
> > > installed on the remote side is a dependency in libvirt-bin, given that
> > > virt-manager is not required on the remote side.
> > >
> > >>> 1) libvirt-bin calls /bin/nc.openbsd, not elegant, but it avoids any
> > >>>    problem in an automatic way
> > >>
> > >> This would break non Debian systems. We could check for nc.openbsd first
> > >> and then fall back to nc though (which would mean fixing up
> > >> Autodetect-if-the-remote-nc-command-supports-the-q-o.patch) but in that
> > >> case it's probably easier to drop the dependency altogether (which is
> > >> what upstream plans to do).
> > >
> > > I am not sure I have completely understood what you wrote:
> > >
> > > 1) Autodetect-if-the-remote-nc-command-supports-the-q-o.patch was
> > >    introduced because of #573172.  In Debian Both netcat-traditional and
> > >    netcat-openbsd have the -q option, but none of the upstream netcat
> > >    has it [1][2].
> > 
> > Actually, I found another bug which is even more interesting: #564034.
> > There, the netcat-openbsd maintainer (cc:ed) announced that he had
> > restored the original behavior if -q is not given:
> > 
> > --8<---------------cut here---------------start------------->8---
> > netcat-openbsd (1.89-4) unstable; urgency=low
> > 
> >   * Quit immediately after EOF if -q is not given (i.e. make the default
> >     equivalent to -q 0). This is the standard upstream behavior and what
> >     other Linux distributions use. It is different from netcat-traditional,
> >     but compatibility with other versions of OpenBSD netcat is more
> >     important. (Closes: #502188)
> > 
> >  -- Decklin Foster <decklin@red-bean.com>  Sun, 18 Apr 2010 20:05:08 -0400
> > --8<---------------cut here---------------end--------------->8---
> > 
> > So, am I right that we do not need anymore the -q patch if libvirt-bin
> > and virt-manager depends on netcat-openbsd >= 1.89-4?
> 
> No, we still need to support this for interoperability with other Linux
> distributions. There are lots of people using virt-manager on Debian to
> manage remote RedHat, SuSE, whatnot.

And we still need -U which is not supported by netcat-traditional.
 -- Guido

Message #59 received at 614291@bugs.debian.org (full text, mbox, reply):

From: Luca Capello <luca@pca.it>

To: Guido Günther <agx@debian.org>

Cc: 614291@bugs.debian.org, Michael Biebl <biebl@debian.org>, Decklin Foster <decklin@debian.org>

Subject: Re: [Pkg-libvirt-maintainers] Bug#614291: Bug#614291: Unable to establish qemu+ssh connection

Date: Tue, 08 Mar 2011 11:42:03 +0100

[Message part 1 (text/plain, inline)]

Hi there!

On Tue, 08 Mar 2011 11:08:09 +0100, Guido Günther wrote:
> On Tue, Mar 08, 2011 at 11:06:34AM +0100, Guido Günther wrote:
>> On Tue, Mar 08, 2011 at 10:41:57AM +0100, Luca Capello wrote:
>> > Actually, I found another bug which is even more interesting: #564034.
>> > There, the netcat-openbsd maintainer (cc:ed) announced that he had
>> > restored the original behavior if -q is not given:
>> > 
>> > --8<---------------cut here---------------start------------->8---
>> > netcat-openbsd (1.89-4) unstable; urgency=low
>> > 
>> >   * Quit immediately after EOF if -q is not given (i.e. make the default
>> >     equivalent to -q 0). This is the standard upstream behavior and what
>> >     other Linux distributions use. It is different from netcat-traditional,
>> >     but compatibility with other versions of OpenBSD netcat is more
>> >     important. (Closes: #502188)
>> > 
>> >  -- Decklin Foster <decklin@red-bean.com>  Sun, 18 Apr 2010 20:05:08 -0400
>> > --8<---------------cut here---------------end--------------->8---
>> > 
>> > So, am I right that we do not need anymore the -q patch if libvirt-bin
>> > and virt-manager depends on netcat-openbsd >= 1.89-4?
>> 
>> No, we still need to support this for interoperability with other Linux
>> distributions. There are lots of people using virt-manager on Debian to
>> manage remote RedHat, SuSE, whatnot.

Last words on this, maybe I am missing something: as far as I understood
(mostly reading the Debian BTS), the -q patch is something *specific* to
Debian (and FWIW non standard), while upstream OpenBSD netcat works out
of the box without that and libvirt.  So if Debian (plus derivatives,
obviously) was the only one with this problem, as it seemed to me, I do
not see how reverting that patch would affect other distributions.

> And we still need -U which is not supported by netcat-traditional.

Yeah, as I wrote in previous emails, I am aware this is another problem.

Thx, bye,
Gismo / Luca

[Message part 2 (application/pgp-signature, inline)]

Message #64 received at 614291@bugs.debian.org (full text, mbox, reply):

From: Guido Günther <agx@sigxcpu.org>

To: Michael Biebl <biebl@debian.org>

Cc: 614291@bugs.debian.org

Subject: Re: [Pkg-libvirt-maintainers] Bug#614291: Unable to establish qemu+ssh connection

Date: Sat, 14 Jan 2012 22:23:10 +0100

tag 614291 +pending
thanks

On Sun, Feb 20, 2011 at 10:28:53PM +0100, Michael Biebl wrote:
> Am 20.02.2011 22:23, schrieb Michael Biebl:
> > Am 20.02.2011 22:13, schrieb Guido Günther:
> > 
> >> You're using netcat-openbsd? 
> > 
> > Server or Client?
> 
> Nevermind. I just checked the KVM server and netcat-openbsd was not installed.
> Installing it solved the problem.
> I can't reproduce anymore, why netcat-openbsd was removed when dist-upgrading
> from lenny to squeeze.
> 
> 
> That said, would it be possible to provide a more meaningful error message in
> virt-manager?
> I would have never guessed that to be a problem of a missing netcat-openbsd.

Sorry for the delay. The error message now mentions netcat:

	http://anonscm.debian.org/gitweb/?p=pkg-libvirt/virt-manager.git;a=blob;f=debian/patches/0006-Improve-error-message-if-netcat-can-t-forward-Unix-d.patch;h=e704ce64b37b26f8b130725c30b2097a73f77b5c;hb=e18d4f40946598b1bc929fbc401074183ae5b4c9

Cheers,
 -- Guido

Message #71 received at 614291-close@bugs.debian.org (full text, mbox, reply):

From: Guido Günther <agx@sigxcpu.org>

To: 614291-close@bugs.debian.org

Subject: Bug#614291: fixed in virt-manager 0.9.0-5

Date: Sun, 15 Jan 2012 13:02:56 +0000

Source: virt-manager
Source-Version: 0.9.0-5

We believe that the bug you reported is fixed in the latest version of
virt-manager, which is due to be installed in the Debian FTP archive:

virt-manager_0.9.0-5.debian.tar.gz
  to main/v/virt-manager/virt-manager_0.9.0-5.debian.tar.gz
virt-manager_0.9.0-5.dsc
  to main/v/virt-manager/virt-manager_0.9.0-5.dsc
virt-manager_0.9.0-5_all.deb
  to main/v/virt-manager/virt-manager_0.9.0-5_all.deb



A summary of the changes between this version and the previous one is
attached.

Thank you for reporting the bug, which will now be closed.  If you
have further comments please address them to 614291@bugs.debian.org,
and the maintainer will reopen the bug report if appropriate.

Debian distribution maintenance software
pp.
Guido Günther <agx@sigxcpu.org> (supplier of updated virt-manager package)

(This message was generated automatically at their request; if you
believe that there is a problem with it please contact the archive
administrators by mailing ftpmaster@debian.org)


-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Format: 1.8
Date: Sun, 15 Jan 2012 13:49:06 +0100
Source: virt-manager
Binary: virt-manager
Architecture: source all
Version: 0.9.0-5
Distribution: unstable
Urgency: low
Maintainer: Debian Libvirt Maintainers <pkg-libvirt-maintainers@lists.alioth.debian.org>
Changed-By: Guido Günther <agx@sigxcpu.org>
Description: 
 virt-manager - desktop application for managing virtual machines
Closes: 614291
Changes: 
 virt-manager (0.9.0-5) unstable; urgency=low
 .
   * [e18d4f4] Improve error message if netcat can't forward Unix domain sockets
     (Closes: #614291)
   * [d5baa70] console: Fix hang when reconnecting to remote VNC console.
     Cherry-picked from upstream (e18d4f40946598b1bc929fbc401074183ae5b4c9)
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 b7ace2a0d4afb8b83ee00b9226b9ecf4331e1fe7 1045700 virt-manager_0.9.0-5_all.deb
Checksums-Sha256: 
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 01486a42acb351dc87887124e0acbb2f8b40af203f284fb042ccb11570058eda 12685 virt-manager_0.9.0-5.debian.tar.gz
 e4e97906d8d1df806421963b8f880be7da7ec351416db0e5dea4bc714a392e11 1045700 virt-manager_0.9.0-5_all.deb
Files: 
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 a1adffb80e80203ae43ba509071e603a 12685 admin optional virt-manager_0.9.0-5.debian.tar.gz
 3aa642b89a20f0c4be83da9ad8941eb4 1045700 admin optional virt-manager_0.9.0-5_all.deb

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