[libvirt-users] [netcf]IFF_RUNNING flag on a bridge device

[Jianwei Hu]

Hi All,

I have one netcf question, please help me to resolve it, thanks.

I can set a IFF_RUNNING flag to a bridge device which are no interface device attached. What status of a flag on a bridge device in current kernel?(w/o interface), is this a new change in kernel or other component? In netcf, but there is a patch to fix that flag issue, I can't understand it.  

fix wrong status of bridge devices
The IFF_RUNNING flag is not set on a bridge device if there are no devices attached to it. So bridges without attached devices are reported as inactive. Destroying inactive devices leads to an error and thus the device can't be removed (easily) from the operating system. This patch checks if the device is a bridge and if so ignores the IFF_RUNNING flag. 

https://git.fedorahosted.org/cgit/netcf.git/commit/?id=7fa5fa5a1e43e6e2afec68c58b5f43bc916703a6


My testing results of IFF_RUNNING on non-device bridge:

Version:
[root at rhel6 boot]# rpm -q kernel netcf
kernel-2.6.32-468.el6.x86_64
netcf-0.2.4-1.el6.x86_64

[root at rhel6 ~]# brctl show br0
bridge name	bridge id		STP enabled	interfaces
br0		8000.000000000000	no		
[root at rhel6 ~]# ifconfig br0
br0       Link encap:Ethernet  HWaddr 6A:3B:6F:DF:17:A9  
          BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:6 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 b)  TX bytes:468 (468.0 b)

[root at rhel6 ~]# ifconfig br0 up
[root at rhel6 ~]# brctl show br0
bridge name	bridge id		STP enabled	interfaces
br0		8000.000000000000	no		
[root at rhel6 ~]# ifconfig br0
br0       Link encap:Ethernet  HWaddr 6A:3B:6F:DF:17:A9  
          inet6 addr: fe80::683b:6fff:fedf:17a9/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:11 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 b)  TX bytes:866 (866.0 b)