Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

2960X stack ring speed at 20G?

I just received my first shipment of 2960X's and am noticing the stack ring speed isn't showing what I would expect.  I have (6)

WS-C2960X-48LPD-L in a stack.  There are no 2960S' in the stack where it would get downgraded.  Here is the output from a few commands...I would expect the Stack Ring Speed to be 80Gbps and the protocol to be FlexStack-Plus.

Switch#sh sw stack-ring speed

Stack Ring Speed        : 20G

Stack Ring Configuration: Full

Stack Ring Protocol     : FlexStack

Switch#sh sw det

Switch/Stack Mac Address : 7c95.f3ef.1300

                                           H/W   Current

Switch#  Role   Mac Address     Priority Version  State

----------------------------------------------------------

*1       Master 7c95.f3ef.1300     15     4       Ready              

2       Member 5017.fff0.d880     13     4       Ready              

3       Member e8ed.f3b3.3880     11     4       Ready              

4       Member 5017.ff41.e200     9      4       Ready              

5       Member 5017.fff0.eb80     7      4       Ready              

6       Member e8ed.f3b3.3600     5      4       Ready              

         Stack Port Status             Neighbors    

Switch#  Port 1     Port 2           Port 1   Port 2

--------------------------------------------------------

  1        Ok         Ok                6        2

  2        Ok         Ok                1        3

  3        Ok         Ok                2        4

  4        Ok         Ok                3        5

  5        Ok         Ok                4        6

  6        Ok         Ok                5        1

Everyone's tags (1)
3 REPLIES
Hall of Fame Super Silver

Re: 2960X stack ring speed at 20G?

20 Gbps is the correct port speed for a homogeneous 2960X stack. Reference.

The 80 Gbps number from the data sheets is "bandwidth" figured in Cisco's marketing way - two rings full duplex means the bandwidth is 4x the port speed.

New Member

Re: 2960X stack ring speed at 20G?

Thats why my pre-sales guy and I figured it was.  Marketing speak.  You would think that they would say in the show commands that the protocol is actually FlexStack-Plus though!

Hall of Fame Super Silver

Re: 2960X stack ring speed at 20G?

I can't find the presentation right now but there was a similar one on the 3850 that I remember explaining how they came up with the numbers they use to market the stack speed. Probably a partner deep dive session.

Yes, I agree the show command should indicate the "Plus". Maybe you can get the TAC to accept the discrepancy as a cosmetic bug.

Edit - look at BRKARC-3448 on CiscoLive365 re the 3850. Slides 38, 86 and 91 shows how a 40 Gbps port speed translates to "480 Gbps" stack speed. (3 rings eastbound plus 3 rings westbound x 2 due to spatial reuse). I believe the 2960 is similar but with with a single ring eastbound and westbound x 2 for spatial reuse.

Message was edited by: Marvin Rhoads

2520
Views
0
Helpful
3
Replies
CreatePlease to create content