I am trying to bridge between eth2
and br0
from Ubuntu 11.04 within virtual box. There is network bridging to host physical machine.
From the guest OS after bridging I can ping from br0
but not from eth2
. Why?
ping -I eth2 bbc.co.uk
:
PING bbc.co.uk (212.58.241.131) from 172.16.4.186 eth2: 56(84) bytes of data.
From VirtualBox.local (172.16.4.103) icmp_seq=2 Destination Host Unreachable
From VirtualBox.local (172.16.4.103) icmp_seq=3 Destination Host Unreachable
ping -I br0 bbc.co.uk
PING bbc.co.uk (212.58.241.131) from 172.16.4.186 br0: 56(84) bytes of data.
64 bytes from virtual-vip.thdo.bbc.co.uk (212.58.241.131): icmp_req=1 ttl=239 time=31.2 ms
My /etc/network/interfaces is as follows
auto lo
iface lo inet loopback
auto eth2
iface eth2 inet manual
auto br0
iface br0 inet static
address 172.16.4.186
network 172.16.4.255
netmask 255.255.255.0
broadcast 172.16.4.255
gateway 172.16.4.1
bridge_ports eth2
bridge_stp off
bridge_fd 0
bridge_maxwait 0
the gateway is
route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 172.16.4.1 0.0.0.0 UG 100 0 0 br0
172.16.4.0 0.0.0.0 255.255.255.0 U 0 0 0 br0
172.16.4.0 0.0.0.0 255.255.255.0 U 1 0 0 eth3
ifconfig
br0 Link encap:Ethernet HWaddr 08:00:27:4a:08:57
inet addr:172.16.4.186 Bcast:172.16.4.255 Mask:255.255.255.0
inet6 addr: fe80::a00:27ff:fe4a:857/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:2969 errors:0 dropped:0 overruns:0 frame:0
TX packets:267 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:200777 (200.7 KB) TX bytes:28141 (28.1 KB)
eth0 Link encap:Ethernet HWaddr 08:00:27:df:f5:a7
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:36 errors:0 dropped:0 overruns:0 frame:0
TX packets:392 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:3904 (3.9 KB) TX bytes:55700 (55.7 KB)
eth2 Link encap:Ethernet HWaddr 08:00:27:4a:08:57
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:19849 errors:0 dropped:0 overruns:0 frame:0
TX packets:1206 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:1631595 (1.6 MB) TX bytes:114927 (114.9 KB)
eth3 Link encap:Ethernet HWaddr 08:00:27:50:00:2d
inet addr:172.16.4.103 Bcast:172.16.4.255 Mask:255.255.255.0
inet6 addr: fe80::a00:27ff:fe50:2d/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:19515 errors:0 dropped:0 overruns:0 frame:0
TX packets:145 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:1625905 (1.6 MB) TX bytes:17450 (17.4 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:113 errors:0 dropped:0 overruns:0 frame:0
TX packets:113 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:12544 (12.5 KB) TX bytes:12544 (12.5 KB)
Best Answer
That is the intended behaviour. If you connect eth2 to a bridge then eth2 becomes unusable (even with an IP address). You use br0 on the software side, eth0 is used physically.
In general when talking about bridges it makes sense to give the output of
brctl show