StackWisePlus on 3750x

[m.glosson]

Greetings. I just set up a new 3750x stack of four switches and it's working fine. However, the StackWise is running at 32G, not 64G, which, according to the Data Sheet from Cisco, StackWisePlus is supposed to be 64G when in Full-Duplex mode. Of course, the Configuration Guide says it's only 32 Gb/s. Is there is a divide between the marketing and engineering departments? Perhaps it the whole full-duplex-is-twice-the-speed thing, like each FastEthernet port is capable of 200 Mbps? Check it out:

# show version

<snip>

Switch Ports Model              SW Version            SW Image
------ ----- -----              ----------            ----------
*    1 30    WS-C3750X-24       12.2(55)SE1           C3750E-UNIVERSALK9-M
     2 30    WS-C3750X-24       12.2(55)SE1           C3750E-UNIVERSALK9-M
     3 30    WS-C3750X-24       12.2(55)SE1           C3750E-UNIVERSALK9-M
     4 30    WS-C3750X-24       12.2(55)SE1           C3750E-UNIVERSALK9-M

<snip>

# sh switch stack-ring speed

Stack Ring Speed        : 32G
Stack Ring Configuration: Full
Stack Ring Protocol     : StackWisePlus

What gives?

Thanks.

[hobbe · Accepted solution]

Hi

That is true

The stackwise+ consists of two rings.

32 Gb in one ring and 32 in the other = 64 Gb

This is the reason you can release one cable and you will still have 32 Gb in "the ring".

Good luck

HTH

[m.glosson]

So the result of "show switch stack-ring speed" will never show 64G for the output?

[hobbe · Accepted solution]

That is correct.

it will not show 64 since the ring speed is 32, but you have two rings.

it will when it is correctly connected show

Stack ringspeed :32G

Stack ring configuration : full

stack ring protocol : stackwiseplus

full = both stackrings are complete

half = one stackring is not connected

Good luck

HTH