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What is vPC loop avoidance mechanism?
vPC loop avoidance rule states that traffic coming from vPC member port, then crossing vPC peer-link is NOT. allowed to egress any vPC member port; however it can egress any other type of port (L3 port, orphan port.). The only exception to this rule occurs when vPC member port goes down.
What is vPC keepalive?
vPC Peer-Keepalive Link – Connects both vPC peer switches and carries monitoring traffic to/from each peer switch. Monitoring is performed to ensure the switches are both operational and running vPC. vPC Peer Link – Connects both vPC peer switches and carries BPDUs, HSRPs, and MAC addresses to its vPC peer.
How does vPC prevent loops?
The Nexus 7000 hardware has loop prevention logic that drops traffic traversing the peer link (destined for a vPC member port) when there are no failed vPC ports or links. Normally peer-link traffic is non-existent in a normal network and this is never a problem for attaching normal Layer 2 switches or servers.
What is the difference between MLAG and vPC?
MLAG is a public protocol which could be supported by almost every vendor using their own custom rolled implementation, while VPC is a Cisco Nexus specific protocol, not all the vendors could have this technology in hand. Thus, MLAG setup is a bit easier than VPC.
What is CFSoE?
The Cisco Fabric Services over Ethernet (CFSoE) is a reliable state transport mechanism that you can use to synchronize the actions of the vPC peer devices. CFSoE carries messages and packets for many features linked with vPC, such as STP and IGMP. Information is carried in CFS/CFSoE protocol data units (PDUs).
What is the difference between vPC and vPC+?
vPC connects hosts and other devices to the network. vPC+ uses a pair of physical switches, like regular vPC does. vPC+ is different, as it creates a virtual switch. The rest of the fabricpath domain sees the host as connected to this virtual switch.
What is the Cisco Design Guide for VPC loop avoidance?
The Cisco design guide clearly states: “vPC loop avoidance rule states that traffic coming from vPC member port, then crossing vPC peer-link is NOT allowed to egress any vPC member port; however it can egress any other type of port (L3 port, orphan port, …).
What’s the maximum number of ports for a VPC?
Depending on type of line card used for vPC member ports, maximum number of port-channel member ports can vary from 16 to 32: ● vPC with Cisco Nexus M1 Series module line-card: 16 active member ports (8 on peer device 1 and 8 on peer device 2) © 2015-2016 Cisco and/or its affiliates. All rights reserved.
How are peer devices used in VPC domain?
●vPC domain is composed of two peer devices. Each peer device processes half of the traffic coming from the access layer. In case a peer device fails, the other peer device will absorb all the traffic with minimal convergence time impact. ●Each peer device in the vPC domain runs its own control plane, and both devices work independently.