Cisco NX-OS Forwarding Architecture The Cisco NX-OS forwarding architecture is responsible for processing all routing updates and populating the forwarding information to all modules in the chassis. The Cisco NX-OS forwarding architecture consists of multiple components, as shown in Figure 6-6. Figure 6-6 Cisco NX-OS Forwarding Architecture The unicast routing information base (URIB) exists … Read more
vPC Configuration Configuring a basic vPC is a multistep process. The following are the steps to enable a basic vPC configuration on the Cisco Nexus 7000 or 9000 Series switch: Step 1. Enter the global configuration mode. Step 2. Enable the vPC feature. Step 3. Create a vPC domain and enter the vPC domain mode. … Read more
vPC Failure Scenarios The following describes how vPC Nexus switches interact with events triggered by failure of a vPC peer-keepalive link, vPC peer-link, and so on: Figure 4-12 vPC Peer-Link Failure Scenario Figure 4-13 vPC Keepalive Link Failure Followed by a Peer-Link Failure Scenario vPC peer-link and keepalive both fail but only keepalive … Read more
vPC Data Plane Traffic Flow vPC performs loop avoidance at the data plane by implementing certain forwarding rules. The most important forwarding rule for a vPC is that a frame that enters the vPC peer switch from the peer-link cannot exit the switch from a vPC member port. This packet can exit on any other … Read more
vPC Control Plane A vPC uses CFSoE as the primary control plane protocol for vPC. The CFSoE protocol runs on vPC peer-link and performs the following control plane operations: Figure 4-9 illustrates the functions performed by vPC control plane. Figure 4-9 vPC Control Plane Similar to regular port channels, virtual port channels are subject … Read more
vPC Components Figure 4-8 shows the components of vPC along with their naming conventions. Figure 4-8 vPC Components The components used in vPCs are as follows:
Virtual Port Channels A virtual port channel (vPC) allows links that are physically connected to two different Cisco Nexus 7000 or 9000 Series devices to appear as a single port channel by a third device. The third device can be a switch, server, or any other networking device that supports port channels. A vPC can … Read more
Port Channel Compatibility Requirements When you add an interface to a channel group, the NX-OS software checks certain interface and operational attributes to ensure that the interface is compatible with the channel group. If you configure a member port with an incompatible attribute, the software suspends that port in the port channel. You can use … Read more
Port Channel Modes Individual interfaces in port channels are configured with channel modes. When you run static port channels with no aggregation protocol, the channel mode is always set to on. When you run LACP as the aggregation protocol, you must first enable the LACP feature. By default, LACP is disabled. The system automatically takes … Read more
Ethernet Port Channels A port channel bundles physical links into a channel group to create a single logical link that provides the aggregate bandwidth of up to 32 physical links. A port channel logically bonds several physical connections into one logical connection. Port channeling also load-balances traffic across these physical interfaces. From the perspective of … Read more