What Cisco ACI Virtual Edge Is
Beginning with the Cisco APIC Release 3.1(1), the Cisco Application Centric Infrastructure (ACI) supports the Cisco ACI Virtual Edge. Cisco ACI Virtual Edge is the next generation of the Application Virtual Switch (AVS) for Cisco ACI environments. Cisco ACI Virtual Edge is a hypervisor-independent distributed service VM that leverages the native distributed virtual switch that belongs to the hypervisor. Cisco ACI Virtual Edge runs in the user space, operates as a virtual leaf, and is managed by the Cisco Application Policy Infrastructure Controller (APIC).
If you use Cisco AVS, you can migrate to Cisco ACI Virtual Edge; if you use VMware VDS, you can run Cisco ACI Virtual Edge on top of it. Decoupling the Cisco ACI Virtual Edge from the kernel space makes the solution adaptable to different hypervisors. It also facilitates simple upgrades as Cisco ACI Virtual Edge is not tied to hypervisor upgrades. Cisco ACI Virtual Edge implements the OpFlex protocol for control plane communication. It supports two modes of traffic forwarding: local switching and no local switching.
Cisco ACI Virtual Edge Release 1.1(1a) supports only the VMware hypervisor. It leverages the vSphere Distributed Switch (VDS), which is configured in private VLAN (PVLAN) mode.
When network administrators create a Cisco ACI Virtual Edge VMM domain on Cisco APIC, they must associate the domain with a range of VLANs to be used for PVLAN pair association of port groups on the DVS. Server administrators do not need to associate PVLANs to port groups on vCenter because Cisco APIC automatically associates PVLAN pairs with the endpoint groups (EPGs).
EPGs in Cisco APIC are equivalent to port groups in vCenter.
Local Switching Mode
In Local Switching mode, the Cisco ACI Virtual Edge locally forwards all intra-EPG traffic without involving the leaf. All inter-EPG traffic is forwarded through the leaf. In this mode, the Cisco ACI Virtual Edge can use either VLAN or VXLAN encapsulation—or both—for forwarding traffic to the leaf and back. You choose the encapsulation type during Cisco ACI Virtual Edge VMM domain creation.
You can configure a single VMM domain in Local Switching mode to use VLAN and VXLAN encapsulation.
If you choose VLAN encapsulation, a range of VLANs must be available for use by the Cisco ACI Virtual Edge. These VLANs have local scope in that they have significance only within the Layer 2 network between the Cisco ACI Virtual Edge and the leaf. If you choose VXLAN encapsulation, only the infra-VLAN must be available between the Cisco ACI Virtual Edge and the leaf. This results in a simplified configuration. It is the recommended encapsulation type if there are one or more switches between the Cisco ACI Virtual Edge and the physical leaf.
No Local Switching Mode
In No Local Switching mode, the leaf forwards all traffic. In this mode, VXLAN is the only allowed encapsulation type.
Statistics collection is enabled on Cisco ACI Virtual Edge by default. You may see Cisco ACI Virtual Edge faults within the Cisco APIC GUI relating to VM resource use.
Troubleshoot those faults in the VMware vCenter because the Cisco ACI only generates these faults based on information it receives from VMware vCenter.