How to do Microsoft NLB multicast on ACI

[Jay Russell Santos]

Question: Hi All

We need your expertise to help us clarify the NLB configuration on ACI. For standard Cisco switch you need to do Static ARP & MAC Address. How to do this on the ACI?

[Tomas de Leon]

Jay,

It is my understanding that Microsoft NLB is only supported on the standalone version of the N9k and actually is not currently supported in ACI. It works in L2 only BD (multicast mode) and routing happens externally (meaning there needs to be an external router), which we are not currently supporting. 

I looked at the roadmap and I do not see this feature added.  If you have a business case for this feature, please contact your Cisco Account Representative and present you business case so they can present to the Business Unit.

Thanks for using the Cisco Support Community!

T.

[Jay Russell Santos]

Hi Thomas,

Thanks for your reply. Do you have any document that you can provide?

Thanks again.

[Tomas de Leon]

Here is a link which mentions support for unicast NLB on N9K in Standalone mode.

Configure Nexus 9300 Unicast NLB

http://www.cisco.com/c/en/us/support/docs/switches/nexus-9000-series-switches/118951-config-nexus9000-unicast-nlb-00.html

Microsoft Network Load Balancing on Nexus 7000 Configuration Example

http://www.cisco.com/c/en/us/support/docs/ip/multicast/116150-configure-Nexus7000-00.html

Catalyst Switches for Microsoft Network Load Balancing Configuration Example
http://www.cisco.com/c/en/us/support/docs/switches/catalyst-6500-series-switches/107995-configure-nlb-00.html?referring_site=RE&pos=2&page=http://www.cisco.com/c/en/us/support/docs/switches/nexus-9000-series-switches/118951-config-nexus9000-unicast-nlb-00.html

none of these are for ACI since it is not supported.

I hope this helps!

T.

[CSCO11741649]

Hello guys,

I am planning to configure Microsoft NLB on ACI and i  was searching for some more information on the net when i saw this post. Is NLB really not supported in ACI mode?

I was thinking NLB can be confgired with IGMP Snooping and static ARP entries in ACI. Does this make sense to you?

Thanks,

Plamena

[suradech.por]

Hello Plamena,

I've asked this question to Cisco Partner Help Line before and below is their answer.

"ACI Mode does NOT support MS Windows NLB and it is also not on the roadmap. Sorry that I can't give you better news. 

Initially support for this feature was planned and in development, but then they cancelled the development, because of development issues.

Now, I have told the BU that we have a Partner and a Customer that is interested in this feature."

The BU will monitor this and when more and more customers/partners request this feature, they may resume the development."

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Actually I've tried by myself and it worked fine with NLB unicast mode. However I couldn't find a way to make it work with multicate mode. And even you can I think Cisco will not support in case of any problem occur in the future.

Hope this help. 

[toshi5301]

Hi,

I am struggling with the issue you saw before.

>Actually I've tried by myself and it worked fine with NLB unicast mode.

How did you configured NLB Unicast mode on ACI?

Thanks

Toshi

[suradech.por]

Hi Toshi,

Normally for Unicast mode, it works base on unknown unicast flooding and packet will be sent out all switch ports so we do not need additional configuration on switch (or ACI in this case).

Please see these links which well describe how NLB unicast mode and multicast mode work.

http://harun.se/blog/?p=20

http://www.cisco.com/c/en/us/support/docs/switches/catalyst-6500-series-switches/107995-configure-nlb-00.html