CSM

[Roble Mumin]

We are planing to replace the core structure consisting of two redundant c4507R and the css 11506 in use with two 6513 including a CSM.

Several things are not really clear from what i read in the Data Sheets.

1. Througput/Bandwith in the CSS sheet is specified with 40Gb/s the CSM sheet mentioned something about 4 Gb/s. In my opinion the CSM should be more powerful in handling content traffic than the css, is that true?

2. Comparing the CSM + SSLM vs. the CSM-S in a SUP720 Enviroment. Is it still true that the CSM-S is not supported yet. I read something about this in a Data Sheet.

3. Does the CSM offer a similiar mechanism as the arrowpoint loadbalancing algorithm? The arrowpoint distributes the load really well so far and round robin is not an option.

4. The CSM is not fabric enabled if understood that correct. Any plans to change that in the future?

We are trying to improve performance in conjunction with expected load in the future. This and the fact that you always have a shortage of Gigabit Ports on the the css made us think about the 6513/CSM solution.

Can you confirm that this is a step in the right direction concerning performance?

Thanks for reading...

Roble

[Gilles Dufour · Accepted solution]

1/ the CSM is connected to the SUP via a 4Gbps link and therefore the traffic is limited by this factor.

The CSS bus can accept up to 40Gbps, so that's the max throughput you can get.

We can't say that the CSM is by default more powerful than a CSS. Depends what traffic, config, hw setup, ...

2/ correct. Support for CSM-S on Sup720 is expected in may.

3/ are you talking about the ACA algorithm ?

If so, no, there is no such thing on the CSM.

We recommend to use leastconn.

4/ The current CSM will never be fabric enabled.

Next generation loadbalancer will be.

Regarding the performance, as mentioned in Q1, it really depends on the traffic, config, ...

Replacing the 4k with a 6k is definitely going to help but in terms of loadbalancer, without knowing more about the setup it is hard to say.

If your CSS is not fully loaded [6 slots], then the CSM is most probably going to be more powerful.

Regards,

Gilles.

[Roble Mumin]

Thanks for the fast answer Gilles!

A1:

The Troughput of 40Gb/s might be faster on paper but is imho always limited by the single uplink of the css to the core switches. I haven't found a way to create etherchannels between css and a catalyst switch yet. That is what made me think about CSM in the first place.

A2:

The Design to head for now would be SUP720 and CSM + SSLM then?

A3:

Yup i was talking about "balance aca" got something mixed up there. I remember "balance leastconn" was not very effective on the CSS in the eyes of our web/portal guys. Gotta get that sorted out then...

A4:

Any ETA on the new LB Product? Will it be a standalone device or is it also a module for a 6K for example?

Regarding our Enviroment. We have around 500 concurrent users currently being distributed by the LB and predictions are that it could rapidly go up to 5 to 6k once the application is rolled out the way they planned it.

That is what i am preparing for actually.

Roble

[Gilles Dufour · Accepted solution]

1/ Etherchannel is not available on CSS.

But if you have multiple vlan, you can use mulitple GIG links and have more than 4Gbps.

That is not really the limitation of these 2 devices anyway.

It is more concurrent connections, conn/sec, and if you are doing Layer 7 loadbalancing or not.

2/ yes.

3/ .

4/ the next gen should come out within the next 1 to 6 months. It will initially be a module for the 6k and later a standalone version should come out. The good news is that they will run the same software.

Gilles.

[Roble Mumin]

Thanks again!

I try to hold back descisions until i can evaluate the new module then.

Roble

[meditz]

Gilles,

Is the module you are referencing in these threads the ACE module?

Thanks,

[Gilles Dufour]

yes, this is the ACE module.

[meditz]

Thanks

[bdodd]

Buy the ACE module and beg cisco to let you be part of the 16gb test group if you need more bandwidth.