Re: a work for lxc monitor network interface

[Libo Chen <clbchenlibo.chen-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>]

On 2013/12/19 4:16, Serge Hallyn wrote:
> Quoting Libo Chen (clbchenlibo.chen-hv44wF8Li93QT0dZR+AlfA@public.gmane.org):
>> Hello LXC experts,
>>
>> 	lxc tool can set network interface by config, but it is static.
>> In some scene, the network interface will be dynamic created on the host
>> and need be shared to container, but it is not suitable to do by hand,
>> so lxc can not work for it.
>>
>> 	I also know lxc_user_nic() can only do a part of work, but we have
>> two more work:
>> 1. grasp the netlink/uevent message about network interface online
>> 2. config interface attached to container ip address .
>>
>> so it can not fully meet my requirements.
>>
>> 	I want there is a monitor can work for network interface hotplug.
>>
>> 1. read config form config file, it describe monitor which network interface
>>    and what's the network configuration
>> 2. grasp the netlink/uevent message about network interface online on the host
>> 3. create veth pair, put veth attach to container and bridge
>> 4. config the veth attached to container ipaddr
>>
>> 			
>>          	          netlink  create veth pair
>> monitor ---> read config  -------> veth0 attach to container --> config ipaddr
>> 				   veth1 attach to bridge
>>
>> monitor may be the lxc-start or a child forked by lxc-start.
>>
>>
>>  Is this reasonable?  If so, I'd like to do it.
> 
> I'm not quite clear on what you're trying to do, but it sounds like you
> could use a udev rule, triggered on the nic creation, and use lxc-device
> from inside that rule to attach the nic to the container.
> 
hi Serge,

using udev rule is a good idea, but not common. for instance android uses ueventd and
busybox uses mdev, sometimes nothing at all.

so how about lxc itself provides this feature?



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