WS-X6148-FE-SFP with SUP720

WS-X6148-FE-SFP with SUP720

Post by denni » Mon, 19 Feb 2007 22:15:50

Hi all,

for a customer I configure a Cat 6509. Also there is the requirement
for 100base fx uplinks to use a WS-X6148-FE-SFP modul.
I'm not very familar with the 65xx architecture. I heard this makes no
sense to use this modul because it brings the backplane speed
down....!? Is this right ?
And if so, what is the recommended solution to use SUP720 together
with classic interface module class....



WS-X6148-FE-SFP with SUP720

Post by Bod4 » Tue, 20 Feb 2007 01:17:27

Certainly in your case the 6148 will not affect fabric
based cards.

The 6148 conects to the 32G bps (really 16 but
marketing beat engineering) and FAbric
cards connect to the fabric backplane and
run at fabric speeds. No interoperability
issues at all.


WS-X6148-FE-SFP with SUP720

Post by denni » Tue, 20 Feb 2007 05:03:13

so If I really understand I can use this modul without a influence the
performance of any other card !?


WS-X6148-FE-SFP with SUP720

Post by Thrill » Tue, 20 Feb 2007 10:25:11

The previous poster is incorrect. The bus on a 6500 runs at the maximum
speed of the slowest card. If you have a card that only uses the 32Gps bus,
than ALL cards use 32Gbps bus. The fabric is used only if ALL cards in the
chassis are fabric enabled.

61xx and 63xx cards are NOT fabric enabled, 65xx and 67xx cards are fabric

An alternative is to use the WS-X6724-SFP with FastEthernet SFP's. You need
to check which versions of code will support the FE SFP's since they are
relatively new.

Also 32Gbps is very fast, Unless your customer's 6500 is populated with lots
of Gig ports that all run more than 10% sustained utilization, I would not
worry what speed the bus is running at.


WS-X6148-FE-SFP with SUP720

Post by Bod4 » Tue, 20 Feb 2007 12:34:50


That is not what it seems to say here.

This is for Cat OS and is the first document I found,

There is a change in behaviour when non fabric cards
are added but it does not look to be like a fallback
to the lowest speed.

The 32G bus is by the way really a 16G bus by
an reasonable measure.

WS-X6148-FE-SFP with SUP720

Post by Thrill » Thu, 22 Feb 2007 06:04:20

You are correct! I got confused with the switching modes, compact vs.
truncated. Compact can only be used if all cards are fabric enabled,
otherwise you need to use truncated.

Sorry for the misinformation, and I'm happy there was someone out there to
set me straight!