新安裝 14.04，我無法連接到工作的 wifi 網路（「Bricks and Scones」是下面日誌中的存取點名稱）。其他設備（例如我用來發布此內容的 Android）連接得很好。我不確定我的配置有什麼問題。我正在查看系統日誌，但仍然無法弄清楚出了什麼問題。這些警告是什麼意思？
ryan@palms /v/log> tail -f syslog | grep -C5 'warn\|error'
May 11 18:55:18 palms avahi-daemon[730]: Withdrawing address record for 192.168.1.129 on wlan0.
May 11 18:55:18 palms avahi-daemon[730]: Leaving mDNS multicast group on interface wlan0.IPv4 with address 192.168.1.129.
May 11 18:55:18 palms avahi-daemon[730]: Interface wlan0.IPv4 no longer relevant for mDNS.
May 11 18:55:09 palms whoopsie[1292]: online
May 11 18:55:18 palms whoopsie[1292]: offline
May 11 18:55:18 palms NetworkManager[985]: <warn> DNS: plugin dnsmasq update failed
May 11 18:55:18 palms wpa_supplicant[1004]: nl80211: Was expecting local disconnect but got another disconnect event first
May 11 18:55:18 palms dnsmasq[2269]: setting upstream servers from DBus
May 11 18:55:18 palms NetworkManager[985]: <info> Removing DNS information from /sbin/resolvconf
May 11 18:55:18 palms kernel: [ 806.867681] cfg80211: Calling CRDA to update world regulatory domain
May 11 18:55:18 palms kernel: [ 806.873484] cfg80211: World regulatory domain updated:
--
May 11 18:55:18 palms NetworkManager[985]: <info> Activation (wlan0) starting connection 'Bricks and Scones Guest Network'
May 11 18:55:18 palms NetworkManager[985]: <info> (wlan0): device state change: disconnected -> prepare (reason 'none') [30 40 0]
May 11 18:55:18 palms NetworkManager[985]: <info> NetworkManager state is now CONNECTING
May 11 18:55:18 palms NetworkManager[985]: <info> Activation (wlan0) Stage 1 of 5 (Device Prepare) scheduled...
May 11 18:55:18 palms wpa_supplicant[1004]: wlan0: CTRL-EVENT-SCAN-STARTED
May 11 18:55:18 palms NetworkManager[985]: <warn> Connection disconnected (reason -3)
May 11 18:55:18 palms NetworkManager[985]: <info> (wlan0): supplicant interface state: completed -> disconnected
May 11 18:55:18 palms NetworkManager[985]: <info> Activation (wlan0) Stage 1 of 5 (Device Prepare) started...
May 11 18:55:18 palms NetworkManager[985]: <info> Activation (wlan0) Stage 2 of 5 (Device Configure) scheduled...
May 11 18:55:18 palms NetworkManager[985]: <info> Activation (wlan0) Stage 1 of 5 (Device Prepare) complete.
May 11 18:55:18 palms NetworkManager[985]: <info> Activation (wlan0) Stage 2 of 5 (Device Configure) starting...
--
May 11 18:55:39 palms NetworkManager[985]: <info> Activation (wlan0) Stage 4 of 5 (IPv6 Configure Timeout) started...
May 11 18:55:39 palms NetworkManager[985]: <info> Activation (wlan0) Stage 4 of 5 (IPv6 Configure Timeout) complete.
May 11 18:55:40 palms dhclient: DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 10 (xid=0x7609df84)
May 11 18:55:50 palms dhclient: DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 13 (xid=0x7609df84)
May 11 18:56:03 palms dhclient: DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 9 (xid=0x7609df84)
May 11 18:56:04 palms NetworkManager[985]: <warn> (wlan0): DHCPv4 request timed out.
May 11 18:56:04 palms NetworkManager[985]: <info> (wlan0): canceled DHCP transaction, DHCP client pid 4231
May 11 18:56:04 palms NetworkManager[985]: <info> Activation (wlan0) Stage 4 of 5 (IPv4 Configure Timeout) scheduled...
May 11 18:56:04 palms NetworkManager[985]: <info> Activation (wlan0) Stage 4 of 5 (IPv4 Configure Timeout) started...
May 11 18:56:04 palms NetworkManager[985]: <info> (wlan0): device state change: ip-config -> failed (reason 'ip-config-unavailable') [70 120 5]
May 11 18:56:04 palms NetworkManager[985]: <info> NetworkManager state is now DISCONNECTED
May 11 18:56:04 palms NetworkManager[985]: <info> Marking connection 'Bricks and Scones Guest Network' invalid.
May 11 18:56:04 palms NetworkManager[985]: <warn> Activation (wlan0) failed for connection 'Bricks and Scones Guest Network'
May 11 18:56:04 palms NetworkManager[985]: <info> Activation (wlan0) Stage 4 of 5 (IPv4 Configure Timeout) complete.
May 11 18:56:04 palms NetworkManager[985]: <info> (wlan0): device state change: failed -> disconnected (reason 'none') [120 30 0]
May 11 18:56:04 palms NetworkManager[985]: <info> (wlan0): deactivating device (reason 'none') [0]
May 11 18:56:04 palms avahi-daemon[730]: Withdrawing address record for fe80::3623:87ff:fefd:5b57 on wlan0.
May 11 18:56:04 palms avahi-daemon[730]: Leaving mDNS multicast group on interface wlan0.IPv6 with address fe80::3623:87ff:fefd:5b57.
May 11 18:56:04 palms avahi-daemon[730]: Interface wlan0.IPv6 no longer relevant for mDNS.
May 11 18:56:04 palms wpa_supplicant[1004]: wlan0: CTRL-EVENT-DISCONNECTED bssid=7e:d1:c3:ce:2c:9a reason=3 locally_generated=1
May 11 18:56:04 palms NetworkManager[985]: <warn> Connection disconnected (reason -3)
May 11 18:56:04 palms wpa_supplicant[1004]: wlan0: CTRL-EVENT-SCAN-STARTED
May 11 18:56:04 palms wpa_supplicant[1004]: nl80211: Was expecting local disconnect but got another disconnect event first
May 11 18:56:04 palms NetworkManager[985]: <info> (wlan0): supplicant interface state: completed -> disconnected
May 11 18:56:04 palms kernel: [ 852.988624] cfg80211: Calling CRDA to update world regulatory domain
May 11 18:56:04 palms kernel: [ 852.991920] cfg80211: World regulatory domain updated:
（這裡有更長的：http://pastebin.com/EPbp51Dz）
答案1
有點遙遠，但你的日誌有共同的訊息一篇發表在 Zeroset 部落格上。他（和我）的問題是一些適配器和接入點在 N 模式下交互不良。解決方法是停用 N 模式，從而切換到較慢的模式。
從您的日誌來看，您似乎沒有英特爾適配器，但如果有，您可以嘗試 Zeroset 的解決方案：
臨時解決方案
對於臨時解決方案，例如檢查建議的解決方案是否對您的設定有幫助，請重新加載無線網路帶選項的內核模組 11n_禁用設定為 1，以停用 802.11N，例如：
sudo sh -c 'modprobe -r iwlwifi && modprobe iwlwifi 11n_disable=1'系統會要求您輸入 sudo 密碼，因為您需要 root 權限才能重新載入核心模組。
永久解決方案
若要在驅動程式中永久停用 802.11N，請新增下列行
options iwlwifi 11n_disable=1到
/etc/modprobe.d/iwlwifi.conf
這裡的「臨時」是指重啟後就會恢復。
有時您必須像上面一樣先停用 802.11N，然後重新啟用它才能解決問題
答案2
我也遇到了類似的問題，但是不設備可以連接，甚至可以使用乙太網路。我將我的解決方案放在這裡，因為這是錯誤訊息的最佳谷歌結果。
我解決了這個問題關閉路由器並重新開啟。
因此，對於像我這樣的聰明人來說，他們開始檢查日誌來診斷問題，然後查看Connection disconnected (reason -3)、還沒有嘗試重新啟動路由器...在谷歌搜尋之前先這樣做。