[c-nsp] Nexus 5K optimisation for iSCSI traffic

[John Gill]

It would be filter toward the FEX ports on your blade switches, but not 
on the FEX ports themselves. Whether you turn STP off or not on the 
blades, the FEX doesn't know. Just remembering if you create a loop, you 
no longer have the protection of STP; you are intentionally tricking the 
FEX into not knowing there is a switch downstream.

Regards,
John Gill
cisco

On 8/5/11 9:59 AM, Matthew Melbourne wrote:
> Thanks for that - that's another issue we've encountered. I am hoping
> we can implement bpdufilter on the FEX ports (as well as disabling STP
> on downstream switches).
>
> On 5 August 2011 14:12, Brad Hedlund (brhedlun)<brhedlun at cisco.com>  wrote:
>> Note that the FEX will disable any port that receives a BPDU, by design in hardware.  You will need to disable STP on the blade-switch-to-FEX links for this to work. If it's Cisco blade switches you can use Flex Links.
>>
>> Cheers,
>> Brad
>> http://bradhedlund.com
>>
>> Sent from my iPad
>> (please excuse brevity, typos)
>>
>> On Aug 5, 2011, at 6:08 AM, "Matthew Melbourne"<matt at melbourne.org.uk>  wrote:
>>
>>> Hi,
>>>
>>> We're implementing two pairs of N5Ks (and downstream N2k FEXes) to act
>>> as separate iSCSI SAN fabrics, with SAN heads attached directly to
>>> N5Ks and host ports (and downstream integrated blade switches)
>>> connecting to the FEXes. Does anyone have any real-world experience of
>>> using N5Ks for a large iSCSI deployment. I have enabled jumbo frames
>>> through a network-qos policy-map as an obvious first-step, but wonder
>>> whether anything can be optimised by tuning buffer sizes to
>>> accommodate the bursty nature of iSCSI (etc)? This switches will only
>>> be switching iSCSI traffic.
>>>
>>> Cheers,
>>>
>>> Matt
>>>
>>> --
>>> Matthew Melbourne
>>> _______________________________________________
>>> cisco-nsp mailing list  cisco-nsp at puck.nether.net
>>> https://puck.nether.net/mailman/listinfo/cisco-nsp
>>> archive at http://puck.nether.net/pipermail/cisco-nsp/