[Pkg-samba-maint] Bug#479512: samba: locks up when cups server unresponsive

[Michal Suchanek]

On 08/06/2008, Steve Langasek <vorlon at debian.org> wrote:
>
> FWIW, I can only confirm this bug if cupsys is *not* running on localhost.
>
>  If it is running, then libcupsys by default uses the unix socket
>  /var/run/cups/cups.sock, and samba is able to connect in spite of any
>  firewalling.

Then it is not that bad because people with relatively standard
configuration should only experience the problem when they do have a
remote cups server that fails.

Firewalling lo was really only an omission in the firewalling script.
I do not care about it either way because I do not use it but there
are certainly some programs that might expect it to work.

>
>
>  > I never had cups running but the question if the server is actually
>  > running is irrelevant when the packets are dropped by networking
>  > (because they are not to a service I intend to run).
>
>  Dropping packets instead of rejecting them is a pathological firewalling
>  policy.  I strongly recommend against doing this.

What is a good firewalling policy is a matter of taste, there are
advantages and disadvantages but calling a policy pathological is too
strong an assertion IMHO.

>
>  > The problem occured with localhost but I would expect there is an
>  > option for using remote cups, and networking problems could have
>  > similar results.
>
>  Yes, you can configure samba to use a remote cups server by setting
>  ServerName in /etc/cups/client.conf.  But why would you ever do that if you
>  didn't actually intend to point CUPS at a viable server...?

Sure, but there is the possibility that someone points to a viable
server and the server or network fails, there is a change in network
or server configuration, etc.

The cups server may be even managed by somebody else on a larger network.

Thanks

Michal