Bug 8686

Summary: ESSID truncated sometimes
Product: Networking Reporter: Victor Porton (porton)
Component: WirelessAssignee: networking_wireless (networking_wireless)
Status: REJECTED WILL_NOT_FIX    
Severity: normal CC: dsd
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: 2.6.21.5 Subsystem:
Regression: --- Bisected commit-id:

Description Victor Porton 2007-06-28 05:20:45 UTC
Most recent kernel where this bug did not occur:
Distribution: Debian/testing
Hardware Environment: Celeron, a USB card managed by zd1211rw driver
Software Environment:
Problem Description:

New information:
** This bug persists with wireless-tools 29.pre21.

However personally for me it is better reproduciable
with version 28.

>The command
># iwconfig eth0 essid default
>randomly sets ESSID either to "default" or to "d".
>
>I did some attempts to debug it myself but give up. However
>it seems for me that the bug is in the kernel not in
>iwconfig utility. Well, I suppose it may be version
>incompatibility.
>
>wireless-tools 28
>Linux 2.6.21.5
>eth0 is a USB card managed by zd1211rw driver.
>
>$ iwconfig --version
>iwconfig  Wireless-Tools version 28
>          Compatible with Wireless Extension v11 to v20.
>
>Kernel    Currently compiled with Wireless Extension v22.
>
>eth0      Recommend Wireless Extension v20 or later,
>          Currently compiled with Wireless Extension v22
Comment 1 Victor Porton 2007-07-01 07:28:53 UTC
This bug persists with wireless-tools 29.pre22.
Comment 2 Daniel Drake 2007-07-02 10:46:58 UTC
This is a softmac bug, with a simple workaround: don't attempt to set the ESSID before bringing the interface up.
Comment 3 Victor Porton 2007-07-02 11:32:01 UTC
Subject: Re:  ESSID truncated sometimes

This workaround cannot be used with DHCP.

>------- Comment #2 from dsd@gentoo.org  2007-07-02 10:46 -------
>This is a softmac bug, with a simple workaround: don't attempt to set the
>ESSID
>before bringing the interface up.
>
Comment 4 Daniel Drake 2007-07-02 12:08:26 UTC
I suggest you use a DHCP client that doesn't mess with interface state (e.g. http://dhcpcd.berlios.de/)

DHCP clients that bring the interface down will cause you other problems even if this bug gets fixed. Such clients are not compatible with softmac-based drivers and a few others.
Comment 5 Victor Porton 2007-07-02 12:43:03 UTC
>------- Comment #4 from dsd@gentoo.org  2007-07-02 12:08 -------
>I suggest you use a DHCP client that doesn't mess with interface state (e.g.
>http://dhcpcd.berlios.de/)
>
>DHCP clients that bring the interface down will cause you other problems even
>if this bug gets fixed. Such clients are not compatible with softmac-based
>drivers and a few others.

I'm not going to bring interface down except of when powering off the computer.

Well, indeed I have random system bug when Internet ceases to work and pinging my router (192.168.0.1) produces something like "Network unreachable" error. I'm lost what's its cause. I hope that these network hangings will disappear as soon as truncated ESSID bug will be fixed.
Comment 6 Daniel Drake 2007-07-02 16:19:26 UTC
(In reply to comment #5)
> I'm not going to bring interface down except of when powering off the
> computer.

That's fine. Make sure you use a DHCP client which also doesn't bring the interface down, otherwise this will cause you problems (including the truncated ESSID)

> Well, indeed I have random system bug when Internet ceases to work and
> pinging
> my router (192.168.0.1) produces something like "Network unreachable" error.
> I'm lost what's its cause. I hope that these network hangings will disappear
> as
> soon as truncated ESSID bug will be fixed.

The truncated ESSID bug probably won't be fixed. softmac is unmaintained. Use the workaround: always bring the interface up before using it, and don't use any software which brings it down.
Comment 7 Victor Porton 2007-07-04 04:57:08 UTC
>the workaround: always bring the interface up before using it, and don't use
>any software which brings it down.

OK, it works with this workaround. Here is the real example of working /etc/interfaces for a DHCP managed zd1211 wireless network card:

iface eth0 inet manual
  up ifconfig eth0 up
  up iwconfig eth0 essid default mode Managed ap 00:C0:02:0A:C7:3E
  up dhclient eth0
  pre-up iptables-restore < /etc/iptables.up.rules
Comment 8 John W. Linville 2007-09-05 06:41:22 UTC
This requirement will persist in mac80211-based driver as well.