access internet with usb gadget

Using bridge:
   if you do not have bridge-utils, you need install it.
   under ubuntu:
      # apt-get install bridge-utils
   PCside, configure the bridge to let pc act as the virtual bridge :
      (only once for below)
      # brctl addbr br0 -- add one new bridge as br0
      # brctl addif eth0 -- add the interface as eth0 for pc
lan
      (after the usb gadget active, else there will be no usb0 virtual
network)
      # brctl addif usb0 -- add the interface as usb0 connect
with beagleboard

   Beagle board using dhcp to get the IP address since it already
bridged
      # udhcpc -i usb0

   Now you are free to access internet.
   NOTES: need to set proxy if you inside private network as:
      # export set http_proxy=PROXY_SERVER_IPADDRESS:PORT

I followed and got the following trace:

brctl addbr br0
brctl addif br0 usb0
brctl addif br0 eth0

and checking the ifconfig -a:

root@tthtlc-desktop:~# ping 10.10.1.153
root@tthtlc-desktop:~# ifconfig -a
br0 Link encap:Ethernet HWaddr 0a:3e:fa:39:8d:41
          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)

eth0 Link encap:Ethernet HWaddr 00:18:f3:b4:7e:ff
          inet addr:10.10.1.155 Bcast:10.10.1.255 Mask:255.255.255.0
          inet6 addr: fe80::218:f3ff:feb4:7eff/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
          RX packets:11576 errors:0 dropped:0 overruns:0 frame:0
          TX packets:10021 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:11526200 (11.5 MB) TX bytes:1576172 (1.5 MB)
          Interrupt:17

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:110 errors:0 dropped:0 overruns:0 frame:0
          TX packets:110 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:9676 (9.6 KB) TX bytes:9676 (9.6 KB)

pan0 Link encap:Ethernet HWaddr 16:62:a5:45:2e:7f
          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)

usb0 Link encap:Ethernet HWaddr f2:7c:70:c2:e0:6d
          inet6 addr: fe80::f07c:70ff:fec2:e06d/64 Scope:Link
          UP BROADCAST MULTICAST MTU:1500 Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:0 (0.0 B) TX bytes:90 (90.0 B)

root@tthtlc-desktop:~# udhcpc -i usb0
udhcpc (v0.9.9-pre) started
Sending discover...
Sending discover...
Sending discover...
Lease failed:
Sending discover...
Sending discover...
Sending discover...
Lease failed:
Sending discover...
Sending discover...
Sending discover...
Lease failed:

any clue?

generally, immediately after i did the "brctl addbr" command, as shown
below, my connection with the gateway (10.10.1.153) will be
disconnected:

brctl addbr br0
root@tthtlc-desktop:~# brctl addif br0 eth0
root@tthtlc-desktop:~# brctl addif br0 usb0
root@tthtlc-desktop:~# ping 10.10.1.153
PING 10.10.1.153 (10.10.1.153) 56(84) bytes of data.
^C
--- 10.10.1.153 ping statistics ---
3 packets transmitted, 0 received, 100% packet loss, time 2015ms

why?

to send this posting out to internet, i have to remove the bridge br0
via "brctl delbr br0".