Question about 10GBs connections

[Colin Higgins]

I want to do VSS with two 10GBs connections between 2 6500 series switches.

What if I "mix and match" the media transmission types by using the 10GBs fiber connection on the Supervisor 2T and a copper 10GB connection on a copper 10GB blade (the 16 port?). Are there any caveats to port channeling interfaces using different media types?           

[Reza Sharifi]

If you want to mix and match by using a port from the 16 port line card (copper or fiber) you have to configure that port in performance mode because that blade is oversubscribed 4:1.

Have a look at this doc for more info:

http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps708/qa_cisco_catalyst_6500_series_16port_10gigabit_ethernet_module.html

HTH

[Colin Higgins]

So I will lose 3 out of 4 ports if I enable performance mode on the group?

Is this also true for other 10GBs line cards, such as the 10 port fiber 10GB card?

is there any issue with mixing fiber and copper in the VSL port-channel?

[Reza Sharifi · Accepted solution]

So I will lose 3 out of 4 ports if I enable performance mode on the group?

correct

Is this also true for other 10GBs line cards, such as the 10 port fiber 10GB card?

There is no 10 port line card.  There is 8 port 10Gig.  If you use the 8 port 10Gig, you don't have to configure anything.  I recommend using this card.

is there any issue with mixing fiber and copper in the VSL port-channel?

As long as there is no speed mismatch there is no issue, but most people use fiber for both VSL links.

Cisco recommends using both 10gig ports from the sup or one from sup and one from line card.

HTH

[Colin Higgins]

Great: thanks for the heads up on the performance issue with the 16 port GB card--I haven't used that card and wasn't aware of the issue.

[Leo Laohoo]

So I will lose 3 out of 4 ports if I enable performance mode on the group?

Hold on here for a minute.  This does NOT add up.

You are using Sup2T right?  So what's your 10Gbps line card you are using?

If you are talking about 16-port 10 Gbps then you'll problem be talking about the WS-X6816-10G-2T  fibre-based 10 Gbps line card or the WS-X6816-10T-2T copper based 10 Gbps line card.

This means that if over-subscription mode is enabled, your over-subscription rate is 2:1 (instead of 4:1, sorry Reza).

See also WS-X6904-40G-2T.

[Reza Sharifi]

Hi Leo,

It is still 4:1

from sup-2T QOS architecture doc:

The WS-6816-10G line card is 4:1 oversubscribed  and has a 40 Gb connection to the switching fabric. It can operate in  two modes: performance mode and oversubscription mode.

here is the link:

http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps708/white_paper_c11-652042.html

HTH

[Leo Laohoo]

It is still 4:1

You're right.