[f-nsp] protecting from network loops due to IP phones

[Raja Subramanian]

On Thu, May 26, 2011 at 1:26 AM, Jared Valentine <hidden at xmission.com> wrote:
> Look at "loop detect", strict or loose mode (depending on your particular
> environment).  It can be run side-by-side with STP or by itself.

Thanks for the tip!

Loose Mode is what is applicable in our environment.  We have near fully
populated SX1600s with ~200 VLANs and 150 phones per chassis.  Any
comments on the system performance impact on enabling Loose Mode
on such a setup?  Other than possibly higher CPU utilization, do you foresee
any other impact?

FastIron Config Guide:

<quote>
Brocade recommends that you limit the use of Loose Mode. If you have a
large number of VLANS, configuring loop detection on all of them can
significantly affect system performance because of the flooding of
test packets to all configured VLANs. An  alternative to configuring
loop detection in a VLAN-group of many VLANs is to configure a
separate VLAN with the same tagged port and configuration, and enable
loop detection on this VLAN only.
</quote>


Thanks again in advance.

- Raja