[Lxc-users] Making LXC accept an already open network interface—or other options

[David Serrano]

On Tue, May 10, 2011 at 16:36, Serge Hallyn <serge.hallyn at canonical.com> wrote:
>
> 1. tell it to give you a normal network interface
>
>  lxc.network.type=veth
>  lxc.network.link=br0
>  lxc.network.flags=down
>
> 2. bring up the container
> 3. bring down the normal interface
> 4. Continue here with passing veth1 into the container.

Thank you.

We're almost there. With this configuration, now there's only lo and
eth0 inside the container indeed. Then I:

host# ip link set veth1 netns $pid
container# ip link del eth0
container# ip link set veth1 name eth0
container# ifconfig eth0 10.1.0.253 up
container# ping 10.1.0.101    ## address of br0 in the host
PING 10.1.0.101 (10.1.0.101) 56(84) bytes of data.
>From 10.1.0.253 icmp_seq=1 Destination Host Unreachable
>From 10.1.0.253 icmp_seq=2 Destination Host Unreachable
>From 10.1.0.253 icmp_seq=3 Destination Host Unreachable

If I bring up eth0 before deleting it and putting veth1 in its place,
the network works as expected and I can ping the host's br0. But the
veth1-renamed-to-eth0 doesn't want to work. Interestingly:

container# ifconfig eth0
# ifconfig eth0
eth0      Link encap:Ethernet  HWaddr ae:6c:69:6a:f5:08
          inet addr:10.1.0.253  Bcast:10.255.255.255  Mask:255.0.0.0
          UP 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:1000
          RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
container# ip neigh show
10.1.0.101 dev eth0  FAILED
container# arp -an
? (10.1.0.101) at <incomplete> on eth0

You can see that the packet counts remain at 0.


--
David Serrano