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New Member

Why 6500 SUP has to go in particular slot?


Q.1 why it is mandatory to add the 6500 SUP in particular slot?

Q.2 Oversubscription is only port oversubscription or it can be calculated for whole fully loaded chassis with max port capacity?

What is the over subscription ration of 6509-E-SUP720 with DFC? Is it valid question if yes then how we can get the oversubscription figure?

e.g. (a)

Below are the oversubscription ratio for 3560 got it from other forum, however can't confirm on accuracy

Cisco 3560E-12D-E

-Backplane: 60Gbps (Gigabits)

-Switching Fabric: 128Gbps (Gigabits)

-Oversubscription: 2:1

e.g. (b)

On 6500 Port Oversubscription is given below:-

A 16-port 10 Gigabit Ethernet module has a 40-Gbps connection to the fabric so is 4:1 (160:40) oversubscribed.



Everyone's tags (1)

Why 6500 SUP has to go in particular slot?

I believe the Supervisor's connection to the chassis is different from that of a normal module.  So to keep costs down, Cisco only placed the supervisor interface in the minimum number of slots.

As for the other questions, I'm not doing your homework for you for free

New Member

Why 6500 SUP has to go in particular slot?

I have completed my homework, who is gone check it now

1 Gbps       = 1.488 Mpps

720 Gbps  = (720 * 1.488) 1071.36 Mpps

9 slot chassis * 48 = 432 mpps


Oversubcription of the

6509 SUP720-10G-3CXL with DFC = 1 * SUP720-10G-3CXL + 8 * LC WS-X6748-GE-TX

with DFC 

Oversubscription ration:-  432 mpps : 1071.36 mpps

                                    1 : 2.48 or 1:2.5