Out of curiosity, did you happen to upgrade to SLC 5.5 from a previous 
version of SLC 5? I ask because I had this same exact wireless card and 
a similar problem with SIOCSIFFLAGS when I updated my old laptop from 
5.1 to 5.3 a couple of years ago (the thread is here: 
http://listserv.fnal.gov/scripts/wa.exe?A2=ind0904&L=scientific-linux-users&T=0&P=9191 
). You can get rid of the SIOCSIFFLAGS problem by following the 
instructions in that thread, but no matter what I did, the wireless 
simply refused to work. The way I finally solved that problem was by 
reformatting the machine and installing a "clean" version of SL 5.3.

If you already have a clean install, then my only suggestion is to use 
NetworkManager. The Intel 4965 card has never worked form me with 
ifconfig -- not with SL 5.1 and not with SL 5.3. There must be some way 
to make it happen, but NetworkManager is so much easier (it generally 
works out-of-the-box).

-- Aram


On 9/13/2011 12:55 PM, vivek chalotra wrote:
> I have scientific linux cern 5.5 installed in my hp compaq 8510w laptop..
>
> I am getting the following error on activating the wlan0 device:
>
> [root@localhost ~]# ifconfig wlan0 up
> SIOCSIFFLAGS: No such file or directory
>
> Contents of /lib/firmware are:
> [root@localhost ~]# cd /lib/firmware/
> [root@localhost firmware]# ls
> iwlwifi-4965-ucode-228.61.2.24
>
>
>
>
> Below are the outputs of lspci command:
>
> [root@localhost ~]# lspci
> 00:00.0 Host bridge: Intel Corporation Mobile PM965/GM965/GL960 Memory 
> Controller Hub (rev 0c)
> 00:01.0 PCI bridge: Intel Corporation Mobile PM965/GM965/GL960 PCI 
> Express Root Port (rev 0c)
> 00:03.0 Communication controller: Intel Corporation Mobile PM965/GM965 
> MEI Controller (rev 0c)
> 00:03.2 IDE interface: Intel Corporation Mobile PM965/GM965 PT IDER 
> Controller (rev 0c)
> 00:03.3 Serial controller: Intel Corporation Mobile PM965/GM965 KT 
> Controller (rev 0c)
> 00:19.0 Ethernet controller: Intel Corporation 82566MM Gigabit Network 
> Connection (rev 03)
> 00:1a.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB 
> UHCI Controller #4 (rev 03)
> 00:1a.1 USB Controller: Intel Corporation 82801H (ICH8 Family) USB 
> UHCI Controller #5 (rev 03)
> 00:1a.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 
> EHCI Controller #2 (rev 03)
> 00:1b.0 Audio device: Intel Corporation 82801H (ICH8 Family) HD Audio 
> Controller (rev 03)
> 00:1c.0 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express 
> Port 1 (rev 03)
> 00:1c.1 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express 
> Port 2 (rev 03)
> 00:1c.4 PCI bridge: Intel Corporation 82801H (ICH8 Family) PCI Express 
> Port 5 (rev 03)
> 00:1d.0 USB Controller: Intel Corporation 82801H (ICH8 Family) USB 
> UHCI Controller #1 (rev 03)
> 00:1d.1 USB Controller: Intel Corporation 82801H (ICH8 Family) USB 
> UHCI Controller #2 (rev 03)
> 00:1d.2 USB Controller: Intel Corporation 82801H (ICH8 Family) USB 
> UHCI Controller #3 (rev 03)
> 00:1d.7 USB Controller: Intel Corporation 82801H (ICH8 Family) USB2 
> EHCI Controller #1 (rev 03)
> 00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev f3)
> 00:1f.0 ISA bridge: Intel Corporation 82801HBM (ICH8M-E) LPC Interface 
> Controller (rev 03)
> 00:1f.1 IDE interface: Intel Corporation 82801HBM/HEM (ICH8M/ICH8M-E) 
> IDE Controller (rev 03)
> 00:1f.2 SATA controller: Intel Corporation 82801HBM/HEM 
> (ICH8M/ICH8M-E) SATA AHCI Controller (rev 03)
> 01:00.0 VGA compatible controller: ATI Technologies Inc M76 [Radeon 
> Mobility HD 2600 Series]
> 01:00.1 Audio device: ATI Technologies Inc RV630/M76 audio device 
> [Radeon HD 2600 Series]
> 02:06.0 CardBus bridge: Ricoh Co Ltd RL5c476 II (rev b9)
> 02:06.1 CardBus bridge: Ricoh Co Ltd RL5c476 II (rev b9)
> 02:06.2 FireWire (IEEE 1394): Ricoh Co Ltd R5C832 IEEE 1394 Controller 
> (rev 03)
> 02:06.3 SD Host controller: Ricoh Co Ltd R5C822 SD/SDIO/MMC/MS/MSPro 
> Host Adapter (rev 20)
> 02:06.4 System peripheral: Ricoh Co Ltd R5C843 MMC Host Controller 
> (rev 10)
> 10:00.0 Network controller: Intel Corporation PRO/Wireless 4965 AG or 
> AGN [Kedron] Network Connection (rev 61)
>
>
>
>
> Any help appreciated .
>
> Thanks and regards
>
> Vvek Chalotra
> GRID Project Associate,
> High Energy Physics Group,
> Department of Physics & Electronics,
> University of Jammu,
> Jammu 180006,
> INDIA.