10 Gigabit Ethernet ports

[insccisco]

I've been looking at switches that have a total of 48 10 Gigabit ports and the closest I got was the 4900M which has 8 fixed and expansion slots where we can put 8-port module cards on each, so this way I can total 24 10 Gigabit ports.

I need a chassis, in other words a single unit, that has a total of 48 10 Gigabit ports. Is there such a monster?

If not, can I purchase those 10 Gigabit modules SUPs and put them in the 6500 or 7000 series switches to come up with a total of 48 10 Gigabit ports?

[Reza Sharifi]

Angel,

There are also 16 port 10Gig modules you could put in your 6500. 3 16 port blades will satisfy you requirement of 48 ports.

HTH

Reza

[Joseph W. Doherty]

What kind of oversubscription, if any, is permissable? On the 6500 chassis, you can easily provide 48 10 gig ports, but generally only if you use the 8 or 16 port 10 gig cards (40 gig per slot).

The Nexus 5020 supports(?) 52 10 gig ports.

The Nexus 7000 supports 32 port 10 gig cards (80 gig per slot).

[insccisco]

what do you mean by oversubscription?

Based on your answers, it does seem that this is doable which is great news.

what's the smallest (in physical size) switch I can get in order to total up 48 ports? and what are the exact cards/modules I should get for those?

[Joseph W. Doherty · Accepted solution]

"what do you mean by oversubscription? "

Since a 6500 provices 40 Gbps per slot, but there are 4, 8 and 16 port 10 gig cards, card port bandwidth to card slot bandwidth ratios are: 1:1, 2:1 and 4:1; more than 1:1 is oversubscription (i.e. the slot can not run all ports concurrently at full port speed).

"what's the smallest (in physical size) switch I can get in order to total up 48 ports? and what are the exact cards/modules I should get for those?"

Probably the 5020 Nexus would be the smallest. Next smallest might be a 6504 with 3 16 port 10 gig cards and a sup720.

[insccisco]

Great info Joseph. Now I understand those ratio numbers I was seeing when I was looking this up.

Bottom line is then I want to stay away from oversubscription?? and get just a 1:1 ratio to take advantage of full speeds??

[Joseph W. Doherty · Accepted solution]

"Bottom line is then I want to stay away from oversubscription?? "

Often not, it depends on usage. Some oversubscription can be fine as rarely do all ports run at 100% for 100% of the time. When such links have more traffic then they can handle, it's queued or dropped, but even then, QoS can determine which traffic might be delayed/dropped or not. Much depends on how you'll be using these ports.

[insccisco]

Great stuff Joseph

[jfraasch]

We had the same decision to make. We have 6513s in the core but decided to go with the Nexus 5010s. Cost is far less. Plus for the application (Oracle Private Interconnect) it made sense for us.

Getting the 5010's for something like $17k. A couple of blades on the 6513 would have been about $25k per 8 10Gbps ports.

The economics just weren't there. Plus the oversubscription on the 6500 is more than on the nexus.

Good luck!

[insccisco]

Hi James,

It's good to know someone already went thru the same situation. The savings are certainly big. What's the exact model of the Nexus you got in order to get 48 10Gigabit ports?

Once again, just like Joseph pointed out, although oversubscription is not bad in every situation, looks like one should stay away from it as much as possible, right? but on the same token, and Joseph also pointed it out, it too depends on what you gonna put on the port.

Let me know... and also why is the oversubscription more on the 6500 than on the Nexus? is it because the 6500s are older?

[jfraasch]

The idea is if you think you will need the full 10Gbps, and in the case of the Oracle Private Interconnect where we are pushing gobs of memory back and forth we just might hit close to 10Gbps, then you don't want to oversubscribe if you don't have to.

Model number you need is:

N5K-5020P-BF (40 10Gbps)

You will need to order the N5K-M1600(=) for the expansion model to get a total of 52(if you get two expansion modules) 10Gbps ports.

Also, be sure to get the SFP+ cables and adapters. They are pretty expensive ($1,000 each).

I attached the quote I got from my vendor for the 5010 plus parts. Should help. Also, it was $11k per switch, not $17 like I said before.

Below is the most important points about the 5020:

Cisco Nexus 5020 56-Port Switch

The Cisco Nexus 5020 is a two-rack-unit (2RU), 10 Gigabit Ethernet, FCoE, and Fibre Channel switch built to provide 1.04 terabits per second (Tbps) throughput with very low latency (Figure 2). It has 40 fixed 10 Gigabit Ethernet and FCoE Small Form-Factor Pluggable Plus (SFP+) ports. The first 16 fixed ports support both 10 Gigabit Ethernet and Gigabit Ethernet in hardware, providing a smooth migration path to 10 Gigabit Ethernet. Two expansion module slots can be configured to support up to 12 additional 10 Gigabit Ethernet and FCoE SFP+ ports, up to 16 Fibre Channel switch ports, or a combination of both. The switch has a serial console port and an out-of-band 10/100/1000-Mbps Ethernet management port. The switch is powered by 1+1 redundant, hot-pluggable power supplies and 4+1 redundant, hot-pluggable fan modules to provide highly reliable front-to-back cooling.

James

[insccisco]

this is it!!

James many thanks for this info. The 5020 it is...

I've done some research and it looks like cisco is the only player out there to have swtiches with these many 10 gigabit ports... but if you know of any other alternatives, let me know

thanks again