[Pkg-utopia-maintainers] Bug#419049: CIFS and use cases

[Raphael Champeimont (Almacha)]

Hi,

You say the description of the package says "is not intended for usage
on servers.", but the problem we have here is for NFS *clients*.

I have experienced this bug on many machines, both with NFS4 and CIFS
(not tried NFS3).
In fact, this problem always happens when network-manager manages an
interface that is used to mount network shares (it is not at all
NFS4-with-quotas-specific, because it's not event NFS-specific). For
example, with CIFS mounts, if and only if network-manager is installed,
when I reboot (or shut down) my machine, I get:
[...]
Stopping network connection manager: NetworkManager.
Stopping DHCP D-Bus daemon: dhcdbd.
[...]
Killing all remaining processes...done.
CIFS VFS: Server not responding          <--- here it waits ~30 seconds
CIFS VFS: No response for cmd 50 mid 10
Deconfiguring network interfaces...
[and here ISC DHCP complains the interface is already down (cannot send
its DHCPRELEASE)]
[...]
and the machine reboots.

The problem obviously is that network-manager puts down the interface
before it is expected by other services (by CIFS/NFS unmounting at least).

About the idea that this use case network-manager+NFS does not exist:
At my work, we have 10 people using laptops running debian etch, every
machine has both an (wired) ethernet card, and a WiFi card. We want to
use our laptops:
1. at work, with the wired network, and we mount NFS and CIFS shares
that contain our collective work documents (we have a DHCP server on
that network, that always give the same IP adresses to our laptops)
2. at home, with a wired network (with DHCP server too)
3. on travel, using wifi

Point 3 makes us need network-manager to avoid the pain of
iwconfig/iwlist. Point 1 and 2 make us need DHCP on the wired interface.

My (dirty and inappropriate for that bug) fix was to add a initscript
that is called first when the machine is rebooted/shut down, and that
umounts all network shares.

I have thought of the following possible solutions (maybe some are in
fact impossible):

Solution 1:
Modify network-manager so that it does not bring down network interfaces
it manages when it exits. With that solution, when the network-manager
daemon stops, it leaves the interfaces up, so then the umounts on
CIFS/NFS can happen properly, and at the end the "Deconfiguring network
interfaces..." step will finally put down the interfaces (as it would
have happened if network-manager was not installed). I known there is
the WPA problem, but network-manager could at least leave up wired
interfaces.

Solution 2:
Make it possible to have, even if network-manager is installed,
interfaces that are DHCP-configured at boot but that are NOT managed by
network-manager. In that case this possibility should be documented in
network-manager's README.Debian (I think of an option tu put in
/etc/network/interfaces on the concerned interfaces), it could also be
said somewhere "You should not use network-manager on interfaces you use
to mount network shares, but you can still use DHCP on these interfaces
by using option blabla."

Almacha