dropping network connection

[Haines Brown]

I have a desktop (Debian Squeeze) that drops its wifi connection to my
AP if I issue the command

# /etc/init.d/networking restart

SIOCSIFLAGS: Input/output error
...
DHCPDISCOVER in eth1
to part 67 interval 8
send packet: Network is down
...
No DHCPOFFERS received.
No working leases on persistent databases - skipping

This loss of connection happens every once in a while on its own,
apparently when my wifi modem DHCP resets the machine network address.
To recover networking I can to reboot, but this is a pain for a machine
that runs continually.

My wifi module ($ lspci | grep Network) is Intersil Corporation Prism
2.5 Waveland chipset, which doesn't provide the module name. After
fishing around ($ /sbin/modinfo | grep description) I eventually found
that it is named orinoco.

I did rmmod and modprobe on orinoco and orinco_pci drivers, and then
restarted the networking. This time the command created a connection
rather than killing it.

How can I prevent this nuisance (it is my wife's machine, and when she
complains I have to interrupt my work)? I don't have network-manager or
wicd installed. Is it a flakey driver, and so should I get a different
wifi card with a different chipset. If so, recommendations would be
appreciated.

Haines Brown

[Alastair Black]

Well, that's the great thing about both Network-Manager and wicd-gtk;
they re-DHCP if it's lost in the middle of something. And they keep
your keys handy.

Is there a desktop? Is it GNOME (then use Network-Manager)? If it's
Xfce, KDE, LXDE or anything else, I would suggest the wicd metapackage.

Alastair

[Haines Brown]

Alastair Black <abqab...@example.net> writes:

> On 01/25/2013 11:25 AM, Haines Brown wrote:

>> This loss of connection happens every once in a while on its own,
>> apparently when my wifi modem DHCP resets the machine network address.
>> To recover networking I can to reboot, but this is a pain for a machine
>> that runs continually.
>>

>> I did rmmod and modprobe on orinoco and orinco_pci drivers, and then
>> restarted the networking. This time the command created a connection
>> rather than killing it.
>>

>> Is it a flakey driver, and so should I get a different
>> wifi card with a different chipset. If so, recommendations would be
>> appreciated.

> Well, that's the great thing about both Network-Manager and wicd-gtk;
> they re-DHCP if it's lost in the middle of something. And they keep
> your keys handy.
>
> Is there a desktop? Is it GNOME (then use Network-Manager)? If it's
> Xfce, KDE, LXDE or anything else, I would suggest the wicd metapackage.

I'm afraid I don't understand. It seems you are saying that if the
problem were a flakey driver, a network manager would automatically
reload it should the connection fail. Is this so?

Haines

[Alastair Black]

I'm saying that the problem *may* be a flaky driver, and that it
*may* be your Access Point. What's the signal level? What's the
setting in the Wireless Emitter for 'Issue the SSID'? Some old
Linksys machines defaulted to 60 seconds for issuing the SSID,
which means that if the signal is lost (a car goes by outside,
someone walks over to the coffeepot, your neighbour logs in on
an adjacent channel...) your NIC might be bereft of a signal for
longer than it can handle. A 100ms beacon from the Wireless
Emitter (Access Point) might take care of it...

Is there a connection loss with any other devices? iPhone,
Tablet, laptop? Where is the wife's system in relation
to the Wireless Emitter?

Network Manager and wicd are really nice gadgets. They are
not needed, but the make life less of a drudgery if you
have to connect / re-connect often.

Alastair

[Haines Brown]

Roger Burton West <roger+ao...@nospam.firedrake.org> writes:

> On 2013-01-26, Haines Brown wrote:
>>I'm afraid I don't understand. It seems you are saying that if the
>>problem were a flakey driver, a network manager would automatically
>>reload it should the connection fail. Is this so?
>

> It'll attempt to re-establish the connection automatically, in much
> the same manner as if you typed "ifup wlan0".

> ...

> So I need to ask: what happens if you do ifdown wlan0 followed by ifup
> wlan0, rather than /etc/init.d/networking restart (which I belive is
> deprecated these days)?

Didn't recover the connection:

# ifdown eth1
...
DHCPRELEASE on eth1 to 192.168.1.254 port 67
...
send_packet: Netweork ios unreachable

# ifup eth1

essentially the same report.

I assume that ifup/ifdown has no effect on the driver, but rebooting
or doing # modprobe orinoco does reload the driver. It seems the driver
is unloading itself, which was why I asked if I needed to replace the
wifi card with one having a different chipset.

Haines Brown

[Haines Brown]

Alastair Black <abqab...@example.net> writes:

> On 01/26/2013 03:46 AM, Haines Brown wrote:
>> Alastair Black <abqab...@example.net> writes:
>>
>>> On 01/25/2013 11:25 AM, Haines Brown wrote:

>>>> I did rmmod and modprobe on orinoco and orinco_pci drivers, and
>>>> then restarted the networking. This time the command created a
>>>> connection rather than killing it.
>>>>
>>>> Is it a flakey driver, and so should I get a different wifi card
>>>> with a different chipset. If so, recommendations would be
>>>> appreciated.
>>
>>> Well, that's the great thing about both Network-Manager and
>>> wicd-gtk; they re-DHCP if it's lost in the middle of something. And
>>> they keep your keys handy.

But I assume that reestablishing a broken connection has nothing to do
with loading the driver. If so, while wicd might be handy, it wouldn't
solve the problem.

>>> Is there a desktop? Is it GNOME (then use Network-Manager)? If it's
>>> Xfce, KDE, LXDE or anything else, I would suggest the wicd
>>> metapackage.

My wife's machine has a GNOME desktop environment; on my own machines I
don't have any such environment. I thought wicd was independent of a
desktop environment, although requires that X server be running. I've
always favored wicd because I've gotten the impression network-manager
can be a real pain.

> I'm saying that the problem *may* be a flaky driver, and that it
> *may* be your Access Point.

My grandson has a Mac laptop somewhat closer and never has a problem
with dropped connection. My wife's machine with the problem is two rooms
away (perhaps 36') from the AP (two walls with aluminum studs) and
before the problem I believe signal strength was sufficient at -23 dBm.

I went to check the signal strength and found once again that my wife's
machine had dropped its connection. This time # rmmod and modprobe on
the module did not help and I had to reboot to recover the
connection. Once I had it I ran

# iwlist eth1 scanning

and found that all cells, including my own AP, have a signal strength of
-11 dBM. Quality is 70/70. My impression is that this -11 dBm is a lot
stronger a signal than I used to get (before the problem of dropped
connection came up), which was -23 dBm (roughtly I used to get 0.01
millewatt but now 0.1 millewatt). What is suspicous is that all cells
have the same strengh, and it seems too high.

> What's the setting in the Wireless Emitter for 'Issue the SSID'?

Interesting. However, I can't find that information when I access the
interface for the Motorola router forced on me by AT&T. I used to use
D-Link router and loved it, but AT&T apparently wants to snoop via their
own device. The Motorolla is dated March 2012.

Haines

[Joe]

On Sun, 27 Jan 2013 11:30:18 -0500
Haines Brown <hai...@histomat.net> wrote:

>
> My wife's machine has a GNOME desktop environment; on my own machines
> I don't have any such environment. I thought wicd was independent of a
> desktop environment, although requires that X server be running. I've
> always favored wicd because I've gotten the impression network-manager
> can be a real pain.
>

It certainly has been. But I have a mobile installation of sid on a
hard drive, and it gets used most often to boot my netbook. On there,
it looks after public wi-fi, my own RADIUS-EAP-TLS wi-fi, an OpenVPN
link, a 3G dongle and wired Ethernet. I also frequently set up temporary
fixed-IP wired links, and apart from needing to remember to remove the
default 'connect automatically' tick, it behaves perfectly. This is
version 0.9.4.0-8 on i386. And yes, I have removed NM from at least one
machine in the past for gross disobedience.

--
Joe

[Haines Brown]

Alastair Black <abqab...@example.net> writes:
> On 01/26/2013 03:46 AM, Haines Brown wrote:
>> Alastair Black <abqab...@example.net> writes:
>>
>>> On 01/25/2013 11:25 AM, Haines Brown wrote:
>>
>>>> This loss of connection happens every once in a while on its own,
>>>> apparently when my wifi modem DHCP resets the machine network address.
>>>> To recover networking I can to reboot, but this is a pain for a machine
>>>> that runs continually.

>>> Well, that's the great thing about both Network-Manager and wicd-gtk;
>>> they re-DHCP if it's lost in the middle of something. And they keep
>>> your keys handy.

I could certainly install wicd, but I get the impression it only
restores a dropped connection. If I can't restore a connection by
/etc/init.d/networking restart, if ifup/down for eth1 (the wireless
interface) does nothing for me, if rmmod/modprobe on the wireless module
has no effect, would installation of a network manager do better?

> I'm saying that the problem *may* be a flaky driver, and that it
> *may* be your Access Point. What's the signal level?

Other machines using the wireless AP have no problem. As I mentioned in
my other post, I get a signal strength of -11 dBm for all reachable APs
in the area. Surely this is not right. Is it evidence something's amiss
with the orinoco module?

The problem is getting more frequent, and I'm anxious to do something
about it before my wife is cut off from the Internet altogether. If it
is the module or chip, I'd change the wireless card. I am using a
Netgear card that happened to around, and so probably should purchase a
card that is known to work well with Debian and does not require the
orinoco module. Gigabyte made some cards that worked very well, but are
no longer readily found. Do you think a new Gibabyte model would work
well?

Haines Brown

[Alastair Black]

On 01/30/2013 07:20 AM, Haines Brown wrote:
>

> The problem is getting more frequent, and I'm anxious to do something
> about it before my wife is cut off from the Internet altogether.

<snippage>

I like West's idea of trying a live CD (try Knoppix).

Also, does your local Sam's Club, Best Buy, etc. have
one of the Cisco (Linksys) USB wireless NIC?

If the problem is getting more frequent, it implies
a capacitor in the device is losing control...

Alastair

[J G Miller]

On Wednesday, January 30th, 2013, at 09:20:52h -0500, Haines Brown stated:

> ifup/down for eth1 (the wireless interface) does nothing for me

???

This confuses me since I thought that eth0, eth1, etc referred
exclusively to ETHernet interfaces whereas Wireless LAN interfaces
were designated wlan0, wlan2, etc

???

[Haines Brown]

Yes, but the orinoco module designates eth1 (ethernet is eth0) as the
wireless inferface. Yes, it is confusing.

I ordered a Gigabyte card because older (and no longer available) models
did so well with linux (plug and play). I'll report back the results of
installing it.

Haines Brown

[J G Miller]

On Thursday, January 31st, 2013, at 06:58:10h -0500, Haines Brown wrote:

> Yes, but the orinoco module designates eth1 (ethernet is eth0) as the
> wireless inferface. Yes, it is confusing.

Thank you for the explanation.

I would guess you already have this page in your bookmarks,
as it may be a useful reference.

<http://www.linuxwireless.ORG/en/users/Drivers/orinoco>