How does vPC avoid loop?
In vPC the loop is avoided at data plane rather than control plane. As per Cisco Design of vPC all data should be forwarded locally and peer-link should not be typically used for data packets.
How can we prevent split brain in vPC?
Best practice is to avoid the split brain scenario all together.
- Configure the peer-link and the keep-alive from entirely independent resources.
- Create a port-channel for the keep-alive.
- Use a dedicated sub-interface for the keep-alive.
What happens if vPC keepalive fails?
vPC keep-alive link failure: If only keep-alive fails, nothing will happen. Only heartbeat between Primary and Secondary node will be lost.
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.
What is Bridge assurance in vPC?
–> Bridge Assurance is one of the STP features that is used to avoid switching loops in your network. –> When bridge assurance is configured on the switch then BPDUs are sent on all interfaces of the switch, including blocked interfaces like the alternate or backup port.
How many vPC can be configured in Nexus switches?
The maximum number of switches in a vPC domain is two. The maximum number of vPC peers per switch or VDC is one. When Static routing from a device to vPC peer switches with next hop, FHRP virtual IP is supported. Dynamic routing adjacency from vPC peer switches to any Layer3 device connected on a vPC is not supported.
What is split brain scenario in vPC?
Basically, in the vPC world, all links are set to forward, and nothing blocks at layer-2 because Spanning Tree is not really in place here. Cisco calls it a “split-brain” scenario. If that vPC peer-link fails for any reason, both switches assume the role of primary. This then creates the forwarding-loop-from-hell.
What is vPC orphan Port suspend?
With vPC orphan-ports suspend configured, an orphan port is also shut down. along with the vPC member ports when the peer-link goes down (figure 98). When the vPC peer-link is restored, configured vPC orphan ports on the secondary vPC peer device are brought up along with vPC member ports.
Does vPC use Spanning Tree?
How vPC Modifies Spanning-Tree. Each spanning-tree enabled switch has a unique Bridge ID. This bridge ID is embedded in each BPDU frame and sent to connected switches. A unique MAC address in the switch is used to create a unique bridge ID.