max delay for stretched ACI fabric

[abourges]

Hi,

...regarding the limitation of a stretched ACI Fabric of 30km's - what's the max delay tolerated by the solution?

When using a DWDM system, longer distances might be possible, if delay's are still acceptable?

Thanks,

Andy

[Muhammad Anser Khan · Accepted solution]

Hi Andy,

30 kms is the validated distance for apic clustering but it does not mean this is a limit.

We can acheive 5ms RTT upto 500 km DWDM.

But there are other limitations of the stretch fabric that you may need to consider e.g. # of leafs, # of spines, # of transit leafs, fabric MAC limitations etc

You may need to communicate with your local CAM and they will provide you the validated limitations.

Regards,

Anser

[abourges]

Hi Anser,

...thanks for your prompt reply. I talked to someone from cisco yesterday and got similar information. There seems to be an enhancement in the next ACI release, which pushes the limit to 10ms RTT, which would allow for ~500km's DWDM connection. We will possibly look into that and stay in contact with cisco for that one ;-)

Regarding the other limitations - we'll need to get more information on that. Part of the problem is, that it seems like cisco hasn't tested larger setups, yet, and thus these are officially not supported. But we will keep on pushing the limits, I guess.... 

Thanks,

andy

[nvermand]

50 kms has been validated for DWDM in the stretched fabric scenario, using QSFP-40G-SR4 and MTP-LC breakout cables. 

Other scenarios are still being tested, so stay tuned.

Nic

[jean-christophe manciot - CCDP]

... like in this "Cisco ACI Stretched Fabric up to 800 KMs - Link failure and convergence times" video with a 10 ms RTT over EoMPLS pseudowires between both fabrics.