How the communication works in ACI

[Network_Sarovani]

Hi Team , 

How the communication between source 10.10.10.49 and destination 10.10.10.52 works if they are configured on the ESXI host and are behind the same interface of ACI LEAF-3 & LEAF-4 switches and on the same vlan . 

Source : 10.10.10.49 

Destination : 10.10.10.52 

From the EP tracker we can see both source and destination are behind the same interface of ACI LEAF-3 & LEAF-4 switches. In this case , when source sends traffic to destination will it come to ACI ? or it will be switched within ESXI ? 

[RedNectar]

Hi @Network_Sarovani ,

Firstly, thanks for the great diagram: (Tip to other readers - put your diagrams pictures inline like CK)

In the case you describe, where BOTH endpoints are...

1. in the same EPG (i.e. the same VLAN on the same vSwitch)
2. in the same subnet

...traffic between the hosts will never leave the vSwitch and therefore never leave the ESXi host.

Now. IF you WANT to control traffic between these two hosts, you have a couple of choices.

1. Put one of the hosts in a different EPG - create a new one just for it if you like
2. Use micro-segmentation (aka uSeg) - which is essentially the same thing, where you create EPGs within EPGs

In both these cases, you will need to create contracts and apply them to allow any communication between them (and probably to other hosts as well)

I hope this helps.

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[a12288]

I believe they will be locally switched at VMware DVS level.

Cisco "used" to have AVS solution to allow us control VM communications inside VMware then VMware offers its own solution to compete with Cisco, so AVS is no longer supported by VMware. But Cisco quite nicely solve this by allowing us to leverage Intra-EPG isolation and uSeg EPG w/ PVLans. They meet our business needs in my ACI environment, and I know some customers are having both ACI and NSX.

Leo