Hi everybody!
I've just install Ubuntu 9.04 on my computer, in the first time everything was OK but recently after I suspend computer, I can't connect to the internet.
When I log on to Window 7 RC i have no problem with the connection, but in Ubuntu sometime the Wired connection disconnected (I don't know why).
AND NOW after I config some files (in /etc/network/interfaces..etc..) i completely cannot connect to the internet.

Here are some information from the terminal that i can provide.
I hope everyone will help me! Thanks a lot!

PS: Now when i go to System/Administrator/Network Tools/Ping and type google.com into the Network Address i get the error:The Address 'google.com' cannot be found. Please enter a valid network address and try again.

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tam@ubuntu:~$ ifconfig
eth0 Link encap:Ethernet HWaddr 00:19:d1:88:c9:16
inet6 addr: fe80::219:d1ff:fe88:c916/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:20 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX bytes:5256 (5.2 KB)

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:16436 Metric:1
RX packets:4 errors:0 dropped:0 overruns:0 frame:0
TX packets:4 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:240 (240.0 B) TX bytes:240 (240.0 B)

tam@ubuntu:~$





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tam@ubuntu:~$ ifconfig -a
eth0 Link encap:Ethernet HWaddr 00:19:d1:88:c9:16
inet6 addr: fe80::219:d1ff:fe88:c916/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:20 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX bytes:5256 (5.2 KB)

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:16436 Metric:1
RX packets:4 errors:0 dropped:0 overruns:0 frame:0
TX packets:4 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:240 (240.0 B) TX bytes:240 (240.0 B)

pan0 Link encap:Ethernet HWaddr b2:c9:ae:53:d9:f1
BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)




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tam@ubuntu:~$ lshw
WARNING: you should run this program as super-user.
ubuntu

*-network DISABLED
description: Ethernet interface
physical id: 1
logical name: pan0
serial: b2:c9:ae:53:d9:f1
capabilities: ethernet physical
configuration: broadcast=yes driver=bridge driverversion=2.3 firmware=N/A multicast=yes




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tam@ubuntu:~$ sudo dhclient eth0
[sudo] password for tam:
Internet Systems Consortium DHCP Client V3.1.1
Copyright 2004-2008 Internet Systems Consortium.
All rights reserved.
For info, please visit http://www.isc.org/sw/dhcp/

Listening on LPF/eth0/00:19:d1:88:c9:16
Sending on LPF/eth0/00:19:d1:88:c9:16
Sending on Socket/fallback
DHCPREQUEST of 10.0.0.10 on eth0 to 255.255.255.255 port 67
DHCPREQUEST of 10.0.0.10 on eth0 to 255.255.255.255 port 67
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 6
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 15
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 21
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 7
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 11
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 1
No DHCPOFFERS received.
Trying recorded lease 10.0.0.10
PING 10.0.0.2 (10.0.0.2) 56(84) bytes of data.

--- 10.0.0.2 ping statistics ---
1 packets transmitted, 0 received, +1 errors, 100% packet loss, time 0ms

No working leases in persistent database - sleeping.



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tam@ubuntu:~$ sudo nano /etc/network/interfaces

auto lo
iface lo inet loopback



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Connection Information // When I've not added the connection "hoangtam" and delete Wired connection 1 I can see this Information(now i can't)

Wired connection1(default)
Interface: Ethernet(eth0)
Hardware Address:00:191:88:C9:16
Driver: e100
Speed: 100Mb/s
Security: None
IP Adress: 10.0.0.10
Broadcast Address: 10.255.255.255
Subnet Mask: 255.0.0.0
Default Route: 10.0.0.2
Primary DNS: 10.0.0.2

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tam@ubuntu:~$ sudo /etc/init.d/networking restart
* Reconfiguring network interfaces... [ OK ]

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Anyone help? I feel very bad, I need to learn programing C language in Ubuntu, and I need google. Please help me.