丢弃无线连接并重新连接Broadcom BCM4321
从昨天开始，最新的发行版，我的网络上通过无线连接的两台Ubuntu计算机每小时都会随机丢弃几次连接。 连接会在几秒钟内重新建立，但会中断下载，浏览和更新。 通过以太网连接的Windows计算机不受这些中断的影响。 在我安装了12.04 Beta版本的前几周没有发生这种情况; 昨天才开始与新的发行版。 事实上，当我输入时，连接掉了两次。
sudo lshw -class network返回：
*-network description: Wireless interface product: BCM4321 802.11a/b/g/n vendor: Broadcom Corporation physical id: 0 bus info: pci@0000:0c:00.0 logical name: eth3 version: 01 serial: 00:16:cf:c9:36:50 width: 64 bits clock: 33MHz capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless configuration: broadcast=yes driver=wl0 driverversion=5.100.82.38 ip=192.168.0.2 latency=0 multicast=yes wireless=IEEE 802.11abgn resources: irq:17 memory:efdfc000-efdfffff memory:e0000000-e00fffff *-network description: Ethernet interface product: BCM4401-B0 100Base-TX vendor: Broadcom Corporation physical id: 0 bus info: pci@0000:03:00.0 logical name: eth2 version: 02 serial: 00:18:8b:ab:dc:fd size: 10Mbit/s capacity: 100Mbit/s width: 32 bits clock: 33MHz capabilities: pm bus_master cap_list ethernet physical mii 10bt 10bt-fd 100bt 100bt-fd autonegotiation configuration: autonegotiation=on broadcast=yes driver=b44 driverversion=2.0 duplex=half latency=64 link=no multicast=yes port=twisted pair speed=10Mbit/s resources: irq:17 memory:ef9fe000-ef9fffff
lsusb返回：
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 001 Device 002: ID 413c:a005 Dell Computer Corp. Internal 2.0 Hub Bus 001 Device 003: ID 0a5c:4500 Broadcom Corp. BCM2046B1 USB 2.0 Hub (part of BCM2046 Bluetooth) Bus 001 Device 004: ID 413c:8126 Dell Computer Corp. Wireless 355 Bluetooth Bus 001 Device 005: ID 0a5c:4502 Broadcom Corp. Keyboard (Boot Interface Subclass) Bus 001 Device 006: ID 0a5c:4503 Broadcom Corp. Mouse (Boot Interface Subclass)
lspci返回：
00:00.0 Host bridge: Intel Corporation Mobile 945GM/PM/GMS, 943/940GML and 945GT Express Memory Controller Hub (rev 03) 00:02.0 VGA compatible controller: Intel Corporation Mobile 945GM/GMS, 943/940GML Express Integrated Graphics Controller (rev 03) 00:02.1 Display controller: Intel Corporation Mobile 945GM/GMS/GME, 943/940GML Express Integrated Graphics Controller (rev 03) 00:1b.0 Audio device: Intel Corporation N10/ICH 7 Family High Definition Audio Controller (rev 01) 00:1c.0 PCI bridge: Intel Corporation N10/ICH 7 Family PCI Express Port 1 (rev 01) 00:1c.1 PCI bridge: Intel Corporation N10/ICH 7 Family PCI Express Port 2 (rev 01) 00:1c.3 PCI bridge: Intel Corporation N10/ICH 7 Family PCI Express Port 4 (rev 01) 00:1d.0 USB controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #1 (rev 01) 00:1d.1 USB controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #2 (rev 01) 00:1d.2 USB controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #3 (rev 01) 00:1d.3 USB controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #4 (rev 01) 00:1d.7 USB controller: Intel Corporation N10/ICH 7 Family USB2 EHCI Controller (rev 01) 00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev e1) 00:1f.0 ISA bridge: Intel Corporation 82801GBM (ICH7-M) LPC Interface Bridge (rev 01) 00:1f.2 IDE interface: Intel Corporation 82801GBM/GHM (ICH7-M Family) SATA Controller [IDE mode] (rev 01) 00:1f.3 SMBus: Intel Corporation N10/ICH 7 Family SMBus Controller (rev 01) 03:00.0 Ethernet controller: Broadcom Corporation BCM4401-B0 100Base-TX (rev 02) 03:01.0 FireWire (IEEE 1394): Ricoh Co Ltd R5C832 IEEE 1394 Controller 03:01.1 SD Host controller: Ricoh Co Ltd R5C822 SD/SDIO/MMC/MS/MSPro Host Adapter (rev 19) 03:01.2 System peripheral: Ricoh Co Ltd R5C592 Memory Stick Bus Host Adapter (rev 0a) 03:01.3 System peripheral: Ricoh Co Ltd xD-Picture Card Controller (rev 05) 0c:00.0 Network controller: Broadcom Corporation BCM4321 802.11a/b/g/n (rev 01)
rfkill list all回报：
0: brcmwl-0: Wireless LAN Soft blocked: no Hard blocked: no 1: dell-wifi: Wireless LAN Soft blocked: no Hard blocked: no 2: dell-bluetooth: Bluetooth Soft blocked: no Hard blocked: no 3: hci0: Bluetooth Soft blocked: no Hard blocked: no
我承认，我不知道如何处理这些问题。 我所知道的是直到昨天，我的连接保持稳定，随着更新，它不断下降和重新连接。
我一直有同样的问题，无线网络保持连接，但几分钟后没有DNS或路由发生。 我必须重新启动以恢复原状。
我所做的是禁用IPV6，到目前为止，连接3小时没有掉线。 不知道如何certificate这是否是解决方案，或者我是否在过去3小时内幸运。
您的Wi-Fi驱动程序未正确安装的可能性很高。 点击窗口（元）按钮并在仪表板上搜索additional drivers 。 启动它并安装任何额外的驱动程序，如果它指示这样做。
如果失败，那么你将不得不检查安装了哪个wi-fi驱动程序。 对于那种类型ctrl+alt+t并输入lspci 。 你会看到司机列表。 查找Network Controller并使用代码从synaptic package manager重新安装驱动程序。 例如bcm43225
尝试禁用WiFi NIC的电源管理：
eth1的示例：iwconfig eth1关闭电源