On a HP ProBook 4420s my wireless connection stopped working after some updates.
I looked in /var/log/boot.msg and saw no trace of the wireless driver being loaded.
So I looked in /var/log/boot.omsg and saw:
[ 11.224842] iwlagn: Intel(R) Wireless WiFi Link AGN driver for Linux, 1.3.27kds [ 11.226111] iwlagn: Copyright(c) 2003-2009 Intel Corporation [ 11.227383] iwlagn 0000:43:00.0: PCI INT A -> GSI 19 (level, low) -> IRQ 19 [ 11.228632] iwlagn 0000:43:00.0: setting latency timer to 64 [ 11.228668] iwlagn 0000:43:00.0: Detected Intel Wireless WiFi Link 6000 Series 2x2 AGN REV=0x74 [ 11.256845] iwlagn 0000:43:00.0: Tunable channels: 13 802.11bg, 24 802.11a channels [ 11.258146] alloc irq_desc for 36 on node -1 [ 11.258147] alloc kstat_irqs on node -1 [ 11.258165] iwlagn 0000:43:00.0: irq 36 for MSI/MSI-X
Then I decided to check:
# locate iwlagn
Some of the results included relevent modules files:
/lib/firmware/iwlwifi-6000-4.ucode /lib/modules/2.6.32.12-0.7-pae/kernel/drivers/net/wireless/iwlwifi /lib/modules/2.6.32.12-0.7-pae/kernel/drivers/net/wireless/iwlwifi/iwl3945.ko /lib/modules/2.6.32.12-0.7-pae/kernel/drivers/net/wireless/iwlwifi/iwlagn.ko /lib/modules/2.6.32.12-0.7-pae/kernel/drivers/net/wireless/iwlwifi/iwlcore.ko
I found (after trying to manually modprobe the modules) I was getting this error in dmesg:
# dmesg
[ 1181.314606] iwlcore: Unknown parameter `led_mode'
Googling the error led me here:
http://centos.org/modules/newbb/viewtopic.php?topic_id=30883&forum=39
So then I investigated and realized I had to go to:
/etc/modprobe.d/50-hp-preload-led.conf
and comment out the line with
#options iwlcore led_mode=1
This is basically because the driver does not support that option. If you run:
modinfo -F parm iwlagn
the led_mode parameter is not there.
Hope this helps.
PS: The package that did this to me was sled11-branding-hp-bnb-1-0.116.1.