Feature #5616
open
Incorrect Wireless Channel
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Description
I appear to have found a bug in the wireless configuration in pfSense. This problem did not appear until I added a second wireless interface to my configuration to allow for a second SSID. I believe it is somehow related. Both wireless networks are in Access Point (hostap) mode. As such, I am specifically defining the channel. Since they are both running on the same wireless adapter in the same band (2.4GHz), I am using the same channel for both interfaces. The reported problem is that a device will attempt to associate to one of the SSIDs. They appear to associate but will not receive an IP address from DHCP. They will also not appear in the wireless client list in pfSense. In researching the problem, I have found that one of the interfaces will be using a random channel rather than the one assigned in the configuration. The output snips below are from a device configured for channel 10.
ifconfig v ath0_wlan0) bssid 04:f0:21:17:41:af
ssid SSID1 channel 10 (2457 MHz 11g ht/40
ifconfig -v ath0_wlan1
ssid SSID2 channel 6 (2437 MHz 11g ht/40+) bssid 06:f0:21:17:41:af
I have modified the XML configuration to test various configurations. I tried a) setting the channel on each interface, b) setting the channel only under the global wireless configuration and not on the interfaces, and c) setting the channel on the interfaces and in the global setting. None of these have resolved the issue.
I am only able to reproduce the problem on certain devices, even though the hardware is identical. The problem also only appears when the configuration is applied on restore or reboot. If you go to the problem interface and hit Save, without making any changes, the ifconfig output will then show the channel as correct and clients will be able to use the network.
One final point, the problem may be related specifically to wlan1 (ex: ath0_wlan1). My initial configurations used two interfaces build from the Wireless list in the interfaces configuration. This resulted in two interfaces: ath0_wlan1 and ath0_wlan2 with the problem interface being ath0_wlan. I recreated the configuration using the real interface (ath0) for one interface and a wireless interface for the second. This created interfaces ath0_wlan0 and ath0_wlan1 with ath0_wlan1. Notice that in both cases that wlan1 was the faulty interface even though it was the first interface in config #1 and the second interface in config #2.
If you need any further information, please let me know.
Thank you,
Jim Lohiser
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