Switch acceleration 4006, SE II, Backplane Channel Module

[odeparis]

Hi,

I feel confused after reading the documentation proposed about configuring switch acceleration on the 4006 SE II with backplane channel module installed.

Description of the swith acceleartion configuration modes shows:

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Option C—Fully meshed interconnections between SEs; dual-link load-balancing between SE1 and SE2 and between SE2 and SE3; Gigabit Ethernet uplink port connections.

This mode requires that the Backplane Channel module is installed and that switch acceleration is configured on the supervisor engine.

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And within the Backplance channel module section later on in the same document:

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Note If you want to keep the uplink connections, do not enable switch acceleration on the supervisor engine.

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My question is then the following, to keep the 2 GE uplink on a 4006 SE II + backplane channel module, should I enable or disable swithacceleration?

Thanks

Alain Biu

Sr Network Engineer

[matthew.scala]

Alian,

You're reading the same material.. but about different "options" regarding the different ways to configure switch acceleration. You basically have 4 options when configuring switch acceleration on the 4000 boxes..

1) no switch acceleration

2) fully meshed interconnections between switch engines, but not being able to utilize the gig uplinks

3) same as "option 2", except you'll have dual-link load balancing between switch engine 1 & switch engine 2/switch engine 2 & switch engine 3, and use of your gig uplinks

4) fully meshed interconnections & MULTI link load balancing connections between ALL switch engines, but not being able to utilize gig uplinks

Now.. for option 1 & 2.. no Backplane Channel Module is required. But, for option 3 & 4.. a Backplane Channel Module IS required to be installed in the chassis.

These are the options you have to choose from, choose whichever best suits your current network setup.

Provided is a link on how to enable/disable switch acceleration, what it is, the benefits of the different configurations & so on. Hope this helps...

http://www.cisco.com/en/US/products/hw/switches/ps663/products_configuration_guide_chapter09186a00800d81c7.html

[odeparis]

Jan,

Thanks for your answer. Let me however give more details here as I feel my problem has not been fully answered.

The only configuration that interests me is the following (known as option 3 or C in Cisco's doc):

--------------------------------------snip---------------------------------------------------------

Option C—Fully meshed interconnections between SEs; dual-link load-balancing between SE1 and SE2 and between SE2 and SE3; Gigabit Ethernet uplink port connections.

This mode requires that the Backplane Channel module is installed and that switch acceleration is configured on the supervisor engine.

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Why: I need my 2 GE on the SE II to be operational

My hardware config is as follows:

- 4006 + SEII + Backplane Channel Module

- I use a backplane channel module to be able to use the 2 GE on the SEII

The extract above clearly mentions that switch acceleration should be enabled

BUT now on the same document, when reaching the Backplane Channel Module section, you can read:

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Note If you want to keep the uplink connections, do not enable switch acceleration on the supervisor engine.

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One hand, you are asked to enable switch acceleration if you want to get your 2 GE operational with 4006+SE II+BCM, on the other hand NOT to enable it...

What is the solution?

Thanks

Alain Biu

[efrahim · Accepted solution]

The doc. is misleading.. you don't need switch acceleration configured for the option C.

Hopefully the doc. would be correct soon

[odeparis]

Thanks, makes sense

Alain