On 05/18/2011 08:39 AM, Stephen Hemminger wrote:

On Wed, 18 May 2011 08:19:40 -0700
Ben Greear[off-list ref]  wrote:

quoted

On 05/18/2011 08:17 AM, Stephen Hemminger wrote:

quoted

The first netlink code in the bridge module was to notify
user space implementations of Spanning Tree Protocol about
new ports. It did not handle the case of kernel mode STP
changing states which could be useful for monitoring.

This patch causes RTM_NEWLINK message to occur on kernel
transitions. It does not send message if request was from user
space STP, since that would cause reflection and break existing
API.

So one app monitoring the system won't get updates if another
app makes changes?

Ben

For now, yes. Just don't want to break any existing users
which is more important.

You can get RTM_NEWLINK messages for various reasons..it would
seem a non-buggy program should have no problem dealing with one
more source.

It seems like this code is going to be inconvenient
for anyone wanting to monitor bridges using netlink, and
even if you fix it in the future, there is going to be
backwards compatible hacks that are likely to be quite
ugly!

Thanks,
Ben

-- 
Ben Greear [off-list ref]
Candela Technologies Inc  http://www.candelatech.com