Subject: Re: vlan: update vlan carrier state for admin up/down

From: Ben Greear <[email-masked]>
Date: Fri, 24 Apr 2009 09:39:11 -0700

Suppose that someone has eth0, eth0.2 and eth0.5 admin UP.

Then, sets eth0.5 admin DOWN.

Later they set eth0 down and up for some reason.

Would eth0.5 now go admin UP?

If so, I think that is not a good idea and could possibly be considered
a security issue.  I think instead there should be a new flag for VLANs
that is 'preferred-admin-state'.  To be UP, both the underlying device
and the preferred state must be UP.  That should allow bouncing eth0
w/out affecting the eventual admin state of the VLANs on eth0 in
the example above.

For what it's worth, it seems that other virtual devices, such as VIFS
on a wifi radio, might need the same sort of behaviour.

Thanks,
Ben

-- 
Ben Greear <[email-masked]>
Candela Technologies Inc  http://www.candelatech.com