Selecting Uplink ports on N5K

[jkarkhanis]

Hi,

I am trying to allocate 4 uplinks from N2K to N5K and N5K to N7K. Are there any best practice guidelines for selecting ports (on N5K), based on data plane architecture?

Thanks,

Jayesh

[Lucien Avramov]

Ask yourself how many servers will be connected to the FEX, this will tell you what bw you need for the uplink

2k --> 5k. Each uplink is 10 GB and you can have up to 4 uplinks on the 2148 / 2248.

Then same will go for your uplink to the 7k, how many traffic you will have.

If you have pairs of 7ks / 5ks you can think about vPC.

If you want to go with 4 uplinks from 2k to 5k, and a pair of 5ks, you can have vPC and 2 uplinks from the 2k to each 5k.

I recommend you the following design docs:

http://www.cisco.com/en/US/products/ps9670/products_implementation_design_guides_list.html

Here is how to setup vPC:

https://supportforums.cisco.com/videos/1177

[jkarkhanis]

Thank you for the prompt reply.

I was reading below white paper, in the data plane architecture section (fig 5) it mentions 14 independent UPC control 10 G port. My confusion is, if there is any value add in distributing N2K (4 uplinks to N5K) to diferent UPC's.

http://www.cisco.com/en/US/partner/prod/collateral/switches/ps9441/ps9670/white_paper_c11-462176.html

[Lucien Avramov · Accepted solution]

Sure in case of the very rare scenario that one asic will fail you will have the other ones to rely on, but is there a real added value, considering you can get a replacement devices very quickly, that is the question to ask yourself.

I wouldnt really go into that detail and would connect the fex to what makes sense logically to you. The document you pointed, the UPC section, it's mainly there to show you the architecture of the hardware, I wouldn't really worry about it.

You can see what hardware (called gatos) the 5k is using for each physical port by the following command:

N5K-1# show hardware internal gatos port ethernet 1/1 | include instance|mac

        gatos instance     : 0   ----> instance 0 (1 asic)

        mac port           : 2

        fw_instance        : 2

N5K-1# show hardware internal gatos port ethernet 1/2 | include instance|mac

        gatos instance     : 0

        mac port           : 3

        fw_instance        : 3

N5K-1# show hardware internal gatos port ethernet 1/3 | include instance|mac

        gatos instance     : 0

        mac port           : 1

        fw_instance        : 1

N5K-1# show hardware internal gatos port ethernet 1/4 | include instance|mac

        gatos instance     : 0

        mac port           : 0

        fw_instance        : 0

N5K-1# show hardware internal gatos port ethernet 1/5 | include instance|mac

        gatos instance     : 1  ------> instance 1 (another asic)

        mac port           : 2

        fw_instance        : 2

[jkarkhanis]

Thank you, Lucien.