最近裝了 Ubuntu 12.04 LTS 經常會看到如下的訊息,說明無線網路在不同的國碼(Country Code)之間變動。先前做過 WSU 計劃的經驗知道國碼會決定無線的頻道採用哪些頻率,所以必須設法讓模組載入時,預設固定在某個國碼。先前知道可以用指令 iw (隸屬於套件 iw)來控制,不過想說如果可以在 /etc/modprobe.d 中設定,就不用老是靠指令去改。
Sep 11 08:31:33 jazzbook kernel: [ 206.775604] cfg80211: Regulatory domain changed to country: EC
Sep 11 08:31:33 jazzbook kernel: [ 206.775605] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
Sep 11 08:31:33 jazzbook kernel: [ 206.775607] cfg80211: (2402000 KHz - 2482000 KHz @ 40000 KHz), (N/A, 2000 mBm)
Sep 11 08:31:33 jazzbook kernel: [ 206.775609] cfg80211: (5170000 KHz - 5250000 KHz @ 20000 KHz), (300 mBi, 1700 mBm)
Sep 11 08:31:33 jazzbook kernel: [ 206.775610] cfg80211: (5250000 KHz - 5330000 KHz @ 20000 KHz), (300 mBi, 2300 mBm)
Sep 11 08:31:33 jazzbook kernel: [ 206.775612] cfg80211: (5735000 KHz - 5835000 KHz @ 20000 KHz), (300 mBi, 3000 mBm)
Sep 11 08:31:39 jazzbook kernel: [ 211.943255] ADDRCONF(NETDEV_UP): wlan0: link is not ready
..............
Sep 11 08:31:39 jazzbook kernel: [ 212.845224] cfg80211: Regulatory domain changed to country: US
Sep 11 08:31:39 jazzbook kernel: [ 212.845229] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp)
Sep 11 08:31:39 jazzbook kernel: [ 212.845235] cfg80211: (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2700 mBm)
Sep 11 08:31:39 jazzbook kernel: [ 212.845242] cfg80211: (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 1700 mBm)
Sep 11 08:31:39 jazzbook kernel: [ 212.845248] cfg80211: (5250000 KHz - 5330000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Sep 11 08:31:39 jazzbook kernel: [ 212.845255] cfg80211: (5490000 KHz - 5600000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Sep 11 08:31:39 jazzbook kernel: [ 212.845261] cfg80211: (5650000 KHz - 5710000 KHz @ 40000 KHz), (300 mBi, 2000 mBm)
Sep 11 08:31:39 jazzbook kernel: [ 212.845268] cfg80211: (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 3000 mBm)