Subject: If bridge have no sub-interfaces, it's status may be still with 'RUNNING'

From: yzhu1 <[email-masked]>
Date: Fri, 13 Feb 2015 17:57:45 +0800

Hi, all

I made this test on ubuntu 14.04 with kernel 3,19-rc7:

1. brctl addbr br0

2. ifconfig br0 up

3. ifconfig br0 (br0's status is with 'RUNNING')

4. brctl addif br0 eth0

5. brctl delif br0 eth0

6. ifconfig br0 (br0's status is without 'RUNNING')

When there is no sub-interface, the flag "RUNNING" is missing after the 
last sub-interface is removed.

As such, should we keep "RUNNING" flag after the last sub-interface is 
removed?

Thanks a lot.
Zhu Yanjun