[size=150]新装的14.04 LTS，插网线无法上网，老是弹出 "disconnected-you are now off line " 的消息。但在windows 7下是可以上网的。

是不是哪里需要设置一下？ 哪位大神来解救？无法上网很不方便。。。[/size]

把下面指令 複製 貼進終端機 執行
0. uname -r
1. sudo lspci -knn
2. sudo lshw -numeric -class network
3. sudo ifconfig -a
把結果直接 選取/複製/貼上來

你在Windows下如何上网？是连接路由器即插即用，还是pppoe认证？

第一步：

把结果复制贴上来

第二步：
2-1. 如果是连接路由器即插即用

拔掉网线

系统托盘网络连接图标 - 编辑连接 - 把所有连接删除。

打开终端，执行

插上网线

把新产生的输出全部复制贴上来

2-2. 如果是pppoe认证，安装使用pppoeconf

uname -r

3.19.0-25-generic

sudo lspci -knn


00:00.0 Host bridge [0600]: Intel Corporation 4th Gen Core Processor DRAM Controller [8086:0c00] (rev 06)
Subsystem: Dell Device [1028:05a4]
Kernel driver in use: hsw_uncore
00:01.0 PCI bridge [0604]: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor PCI Express x16 Controller [8086:0c01] (rev 06)
Kernel driver in use: pcieport
00:14.0 USB controller [0c03]: Intel Corporation 8 Series/C220 Series Chipset Family USB xHCI [8086:8c31] (rev 04)
Subsystem: Dell Device [1028:05a4]
Kernel driver in use: xhci_hcd
00:16.0 Communication controller [0780]: Intel Corporation 8 Series/C220 Series Chipset Family MEI Controller #1 [8086:8c3a] (rev 04)
Subsystem: Dell Device [1028:05a4]
Kernel driver in use: mei_me
00:19.0 Ethernet controller [0200]: Intel Corporation Ethernet Connection I217-LM [8086:153a] (rev 04)
Subsystem: Dell Device [1028:05a4]
Kernel driver in use: e1000e
00:1a.0 USB controller [0c03]: Intel Corporation 8 Series/C220 Series Chipset Family USB EHCI #2 [8086:8c2d] (rev 04)
Subsystem: Dell Device [1028:05a4]
Kernel driver in use: ehci-pci
00:1b.0 Audio device [0403]: Intel Corporation 8 Series/C220 Series Chipset High Definition Audio Controller [8086:8c20] (rev 04)
Subsystem: Dell Device [1028:05a4]
Kernel driver in use: snd_hda_intel
00:1c.0 PCI bridge [0604]: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #1 [8086:8c10] (rev d4)
Kernel driver in use: pcieport
00:1c.1 PCI bridge [0604]: Intel Corporation 8 Series/C220 Series Chipset Family PCI Express Root Port #2 [8086:8c12] (rev d4)
Kernel driver in use: pcieport
00:1d.0 USB controller [0c03]: Intel Corporation 8 Series/C220 Series Chipset Family USB EHCI #1 [8086:8c26] (rev 04)
Subsystem: Dell Device [1028:05a4]
Kernel driver in use: ehci-pci
00:1f.0 ISA bridge [0601]: Intel Corporation Q87 Express LPC Controller [8086:8c4e] (rev 04)
Subsystem: Dell Device [1028:05a4]
Kernel driver in use: lpc_ich
00:1f.2 RAID bus controller [0104]: Intel Corporation 82801 SATA Controller [RAID mode] [8086:2822] (rev 04)
Subsystem: Dell Device [1028:05a4]
Kernel driver in use: ahci
00:1f.3 SMBus [0c05]: Intel Corporation 8 Series/C220 Series Chipset Family SMBus Controller [8086:8c22] (rev 04)
Subsystem: Dell Device [1028:05a4]
01:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc. [AMD/ATI] Oland [Radeon HD 8570 / R7 240 OEM] [1002:6611]
Subsystem: Dell Radeon R5 240 OEM [1028:210b]
Kernel driver in use: radeon
01:00.1 Audio device [0403]: Advanced Micro Devices, Inc. [AMD/ATI] Cape Verde/Pitcairn HDMI Audio [Radeon HD 7700/7800 Series] [1002:aab0]
Subsystem: Dell Device [1028:aab0]
Kernel driver in use: snd_hda_intel
03:00.0 PCI bridge [0604]: Texas Instruments XIO2001 PCI Express-to-PCI Bridge [104c:8240]



sudo lshw -numeric -class network


*-network
description: Ethernet interface
product: Ethernet Connection I217-LM [8086:153A]
vendor: Intel Corporation [8086]
physical id: 19
bus info: pci@0000:00:19.0
logical name: eth0
version: 04
serial: 64:00:6a:5b:35:0e
size: 100Mbit/s
capacity: 1Gbit/s
width: 32 bits
clock: 33MHz
capabilities: pm msi bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation
configuration: autonegotiation=on broadcast=yes driver=e1000e driverversion=2.3.2-k duplex=full firmware=0.13-4 latency=0 link=yes multicast=yes port=twisted pair speed=100Mbit/s
resources: irq:30 memory:f7f00000-f7f1ffff memory:f7f39000-f7f39fff ioport:f040(size=32)




sudo ifconfig -a


eth0 Link encap:Ethernet HWaddr 64:00:6a:5b:35:0e
inet6 addr: fe80::6600:6aff:fe5b:350e/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:1154 errors:0 dropped:1 overruns:0 frame:0
TX packets:2251 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:129804 (129.8 KB) TX bytes:457715 (457.7 KB)
Interrupt:20 Memory:f7f00000-f7f20000

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:253 errors:0 dropped:0 overruns:0 frame:0
TX packets:253 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:18737 (18.7 KB) TX bytes:18737 (18.7 KB)

拔掉网线

打开终端，执行


插上网线，令其自动连接，失败

把新产生的输出全部复制贴上来

1. 有線網卡 I217-LM
應該已被驅動
已經有接發資訊包
但是沒有 IPv4 網址
所以無法連通網路


2. 這句話 不明白
插上网线
到底能否上網 ?
2-1. 你上面的 sudo ifconfig -a
有沒有插上網卡 ?
還是 你目前不在單位 在家裡 或 其它地方 ?
2-2. sudo dhclient -v
把結果複製 貼上來

3. Wired connection 1 是 NM-Applet 上面自動幫 eth0 取的別名 別名 可以修改
3-1. 如果自動連線有打勾 移除後 又會自動產生另一個 eth0 的別名
3-2. 把自動連線打勾取消 移除後 可能就不會自動產生另一個 eth0 的別名

4. 到 Windows 7 把 IPv4 設定頁面 擷圖貼上來

拔掉网线，sudo tail -f /var/log/syslog

Sep 9 07:56:55 zhizhou-OptiPlex-9020 anacron[3407]: Updated timestamp for job `cron.weekly' to 2015-09-09
Sep 9 07:57:02 zhizhou-OptiPlex-9020 anacron[3214]: Job `cron.weekly' terminated
Sep 9 07:57:02 zhizhou-OptiPlex-9020 anacron[3214]: Normal exit (2 jobs run)
Sep 9 08:17:01 zhizhou-OptiPlex-9020 CRON[3446]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Sep 9 09:17:01 zhizhou-OptiPlex-9020 CRON[3467]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Sep 9 10:17:01 zhizhou-OptiPlex-9020 CRON[3488]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Sep 9 11:17:01 zhizhou-OptiPlex-9020 CRON[3539]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Sep 9 12:17:01 zhizhou-OptiPlex-9020 CRON[3559]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Sep 9 13:17:01 zhizhou-OptiPlex-9020 CRON[3580]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Sep 9 14:17:01 zhizhou-OptiPlex-9020 CRON[3601]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)



插上网线之后：

Sep 8 16:41:48 zhizhou-OptiPlex-9020 NetworkManager[767]: Ifupdown: get unmanaged devices count: 0
Sep 9 14:57:02 zhizhou-OptiPlex-9020 NetworkManager[767]: <info> (eth0): carrier now ON (device state 20)
Sep 9 14:57:02 zhizhou-OptiPlex-9020 kernel: [89628.602996] e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: Rx/Tx
Sep 9 14:57:02 zhizhou-OptiPlex-9020 kernel: [89628.603009] e1000e 0000:00:19.0 eth0: 10/100 speed: disabling TSO
Sep 9 14:57:02 zhizhou-OptiPlex-9020 NetworkManager[767]: <info> (eth0): device state change: unavailable -> disconnected (reason 'carrier-changed') [20 30 40]

拔掉网线，sudo tail -f /var/log/syslog


Sep 9 07:56:55 zhizhou-OptiPlex-9020 anacron[3407]: Updated timestamp for job `cron.weekly' to 2015-09-09
Sep 9 07:57:02 zhizhou-OptiPlex-9020 anacron[3214]: Job `cron.weekly' terminated
Sep 9 07:57:02 zhizhou-OptiPlex-9020 anacron[3214]: Normal exit (2 jobs run)
Sep 9 08:17:01 zhizhou-OptiPlex-9020 CRON[3446]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Sep 9 09:17:01 zhizhou-OptiPlex-9020 CRON[3467]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Sep 9 10:17:01 zhizhou-OptiPlex-9020 CRON[3488]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Sep 9 11:17:01 zhizhou-OptiPlex-9020 CRON[3539]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Sep 9 12:17:01 zhizhou-OptiPlex-9020 CRON[3559]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Sep 9 13:17:01 zhizhou-OptiPlex-9020 CRON[3580]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)
Sep 9 14:17:01 zhizhou-OptiPlex-9020 CRON[3601]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly)



插上网线后：

Sep 8 16:41:48 zhizhou-OptiPlex-9020 NetworkManager[767]: Ifupdown: get unmanaged devices count: 0
Sep 9 14:57:02 zhizhou-OptiPlex-9020 NetworkManager[767]: <info> (eth0): carrier now ON (device state 20)
Sep 9 14:57:02 zhizhou-OptiPlex-9020 kernel: [89628.602996] e1000e: eth0 NIC Link is Up 100 Mbps Full Duplex, Flow Control: Rx/Tx
Sep 9 14:57:02 zhizhou-OptiPlex-9020 kernel: [89628.603009] e1000e 0000:00:19.0 eth0: 10/100 speed: disabling TSO
Sep 9 14:57:02 zhizhou-OptiPlex-9020 NetworkManager[767]: <info> (eth0): device state change: unavailable -> disconnected (reason 'carrier-changed') [20 30 40]

日志好像不完整？从 Sep 9 14:17:01 到 Sep 9 14:57:02 中间缺了这么多，拔掉网线再插上间隔了多久？为什么中间会有一条 Sep 8 16:41:48 的信息？

让网线处于拔掉的状态，打开终端，执行

然后立刻插上网线，等待‘弹出 "disconnected-you are now off line "’ 的信息，然后把刷出的日志发上来。

===================================

因为信息不完整，先当做通病来处理：
编辑 /etc/default/grub ，在 GRUB_CMDLINE_LINUX_DEFAULT="" 中引号内加上 pcie_aspm=off 字样 两边留空格：

保存，然后执行 sudo update-grub

是单位的机器，网线是即插即用的

插上网线，sudo ifconfig -a

eth0 Link encap:Ethernet HWaddr 64:00:6a:5b:35:0e
BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:1232 errors:0 dropped:3 overruns:0 frame:0
TX packets:2501 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:138805 (138.8 KB) TX bytes:508368 (508.3 KB)
Interrupt:20 Memory:f7f00000-f7f20000

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:364 errors:0 dropped:0 overruns:0 frame:0
TX packets:364 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:28208 (28.2 KB) TX bytes:28208 (28.2 KB)



sudo dhclient -v

Internet Systems Consortium DHCP Client 4.2.4
Copyright 2004-2012 Internet Systems Consortium.
All rights reserved.
For info, please visit https://www.isc.org/software/dhcp/

Listening on LPF/eth0/64:00:6a:5b:35:0e
Sending on LPF/eth0/64:00:6a:5b:35:0e
Sending on Socket/fallback
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 3 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 6 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 14 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 11 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 20 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 20 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 8 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 12 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 17 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 11 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 12 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 14 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 20 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 19 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 19 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 18 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 13 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 13 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 15 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 10 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 14 (xid=0xd4fae005)
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 11 (xid=0xd4fae005)
No DHCPOFFERS received.
No working leases in persistent database - sleeping.


在windows7下面的ipv4设置 ，都是obtain an IP address automatically, obtain DNS server address automatically

所以 你現在不是在單位裡 ?

試試
依序
把你的電腦關機 關閉電源
把你的 Router 關機 關閉電源
等 1 ~ 3 分鐘
把你的 Router 打開電源 啟動 Router
把你的電腦 打開電源 開機
等 登入桌面
再
sudo dhclient -v
sudo ifconfig -a
看看 有沒有改變

提醒
要注意 同一個 Router 有沒有其他人員正在上網

他是说：如果工作正常，插上就能用。即不是pppoe等其它连接方式。

sudo tail -f /var/log/syslog
等弹出disconnected-you are now off line后，
Sep 11 13:49:29 zhizhou-OptiPlex-9020 dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 17 (xid=0x9208f615)
Sep 11 13:49:38 zhizhou-OptiPlex-9020 NetworkManager[744]: <warn> (eth0): DHCPv4 request timed out.
Sep 11 13:49:38 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> (eth0): canceled DHCP transaction, DHCP client pid 2756
Sep 11 13:49:38 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Activation (eth0) Stage 4 of 5 (IPv4 Configure Timeout) scheduled...
Sep 11 13:49:38 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Activation (eth0) Stage 4 of 5 (IPv4 Configure Timeout) started...
Sep 11 13:49:38 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> (eth0): device state change: ip-config -> failed (reason 'ip-config-unavailable') [70 120 5]
Sep 11 13:49:38 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> NetworkManager state is now DISCONNECTED
Sep 11 13:49:38 zhizhou-OptiPlex-9020 NetworkManager[744]: <warn> Activation (eth0) failed for connection 'Auto Ethernet'
Sep 11 13:49:38 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Activation (eth0) Stage 4 of 5 (IPv4 Configure Timeout) complete.
Sep 11 13:49:38 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> (eth0): device state change: failed -> disconnected (reason 'none') [120 30 0]
Sep 11 13:49:38 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> (eth0): deactivating device (reason 'none') [0]
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Auto-activating connection 'Auto Ethernet'.
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Activation (eth0) starting connection 'Auto Ethernet'
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> (eth0): device state change: disconnected -> prepare (reason 'none') [30 40 0]
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> NetworkManager state is now CONNECTING
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) scheduled...
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) started...
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) scheduled...
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Activation (eth0) Stage 1 of 5 (Device Prepare) complete.
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) starting...
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> (eth0): device state change: prepare -> config (reason 'none') [40 50 0]
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) successful.
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) scheduled.
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Activation (eth0) Stage 2 of 5 (Device Configure) complete.
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) started...
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> (eth0): device state change: config -> ip-config (reason 'none') [50 70 0]
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Activation (eth0) Beginning DHCPv4 transaction (timeout in 45 seconds)
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> dhclient started with pid 2758
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Activation (eth0) Beginning IP6 addrconf.
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Activation (eth0) Stage 3 of 5 (IP Configure Start) complete.
Sep 11 13:49:41 zhizhou-OptiPlex-9020 dhclient: Internet Systems Consortium DHCP Client 4.2.4
Sep 11 13:49:41 zhizhou-OptiPlex-9020 dhclient: Copyright 2004-2012 Internet Systems Consortium.
Sep 11 13:49:41 zhizhou-OptiPlex-9020 dhclient: All rights reserved.
Sep 11 13:49:41 zhizhou-OptiPlex-9020 dhclient: For info, please visit https://www.isc.org/software/dhcp/
Sep 11 13:49:41 zhizhou-OptiPlex-9020 dhclient:
Sep 11 13:49:41 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> (eth0): DHCPv4 state changed nbi -> preinit
Sep 11 13:49:41 zhizhou-OptiPlex-9020 dhclient: Listening on LPF/eth0/64:00:6a:5b:35:0e
Sep 11 13:49:41 zhizhou-OptiPlex-9020 dhclient: Sending on LPF/eth0/64:00:6a:5b:35:0e
Sep 11 13:49:41 zhizhou-OptiPlex-9020 dhclient: Sending on Socket/fallback
Sep 11 13:49:41 zhizhou-OptiPlex-9020 dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 3 (xid=0x479e5a0b)
Sep 11 13:49:44 zhizhou-OptiPlex-9020 dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 7 (xid=0x479e5a0b)
Sep 11 13:49:51 zhizhou-OptiPlex-9020 dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 10 (xid=0x479e5a0b)
Sep 11 13:50:01 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> (eth0): IP6 addrconf timed out or failed.
Sep 11 13:50:01 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Activation (eth0) Stage 4 of 5 (IPv6 Configure Timeout) scheduled...
Sep 11 13:50:01 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Activation (eth0) Stage 4 of 5 (IPv6 Configure Timeout) started...
Sep 11 13:50:01 zhizhou-OptiPlex-9020 NetworkManager[744]: <info> Activation (eth0) Stage 4 of 5 (IPv6 Configure Timeout) complete.
Sep 11 13:50:01 zhizhou-OptiPlex-9020 dhclient: DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 15 (xid=0x479e5a0b)



更改grub后，sudo update-grub

Generating grub configuration file ...
Found linux image: /boot/vmlinuz-3.19.0-25-generic
Found initrd image: /boot/initrd.img-3.19.0-25-generic
Found memtest86+ image: /boot/memtest86+.elf
Found memtest86+ image: /boot/memtest86+.bin
Found Windows 7 (loader) on /dev/sda2
done

单位里面的路由器我是操作不了的。。。。。。