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Topic: udhcpc doesn't assign ip address to interface

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Hi all,

I have the following network configuration

root@OpenWrt:~# cat /etc/config/network
# Copyright (C) 2006 OpenWrt.org

config interface loopback
        option ifname   lo
        option proto    static
        option ipaddr   127.0.0.1
        option netmask  255.0.0.0

config interface lan
        option ifname   eth0

and created manually the bridge "br0" interface from the command line as

root@OpenWrt:~# brctl addbr br0
br0: Dropping NETIF_F_UFO since no NETIF_F_HW_CSUM feature.
root@OpenWrt:~# ifconfig eth0 up
root@OpenWrt:~# ifconfig br0 up
root@OpenWrt:~# brctl addif br0 eth0
device eth0 entered promiscuous mode
br0: port 1(eth0) entering learning state
root@OpenWrt:~# udhcpc -i br0
udhcpc (v1.11.2) started
Sending discover...
br0: topology change detected, propagating
br0: port 1(eth0) entering forwarding state
Sending discover...
Sending select for 192.168.7.213...
Lease of 192.168.7.213 obtained, lease time 600

root@OpenWrt:~# ifconfig
ath0      Link encap:Ethernet  HWaddr 06:0C:42:26:66:1F
          UP BROADCAST RUNNING 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)

br0       Link encap:Ethernet  HWaddr 00:08:A2:04:3F:FA
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:5 errors:0 dropped:0 overruns:0 frame:0
          TX packets:3 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:794 (794.0 B)  TX bytes:1214 (1.1 KiB)

eth0      Link encap:Ethernet  HWaddr 00:08:A2:04:3F:FA
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:5 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:100
          RX bytes:794 (794.0 B)  TX bytes:812 (812.0 B)

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          UP LOOPBACK RUNNING  MTU:16436  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)

wifi0     Link encap:UNSPEC  HWaddr 00-0C-42-26-66-1F-00-00-00-00-00-00-00-00-00-00
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:4190 errors:0 dropped:0 overruns:0 frame:482
          TX packets:1688 errors:1512 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:280
          RX bytes:283479 (276.8 KiB)  TX bytes:178946 (174.7 KiB)
          Interrupt:28

When I run "udhcpc -i br0" it recieves an IP address but ifconfig shows that the interface is not assigned with ip address and
cat /tmp/resolv.conf shows nothing.

If I include "option type bridge" and" option proto dhcp" in /etc/config/network the interface br-lan got assigned with a dhcp ip address.

can anybody explain me why is the difference that ip address is not assigned when executing udhcpc from command line ?

Thanks
Sara

(Last edited by sara on 24 Jun 2009, 12:20)

udhcpc checks whether the interface has "option proto dhcp" set. If not, it will refuse to set the ip then.

~ JoW

(Last edited by jow on 24 Jun 2009, 12:22)

if so udhcpc refuses, how can I over come to get the interface assign with ip address ?

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