One of the most impressive network design options available on the Catalyst 6500 is the use of VSS. Connecting two Catalyst 6500s equipped with Sup2Ts creates a virtual switch, adding each switch’s performance while operating as a single switch thus eliminating spanning tree in favor for active-active links. We configure two Catalyst 6500s via VSS. We measure throughput performance to verify that VSS throughput rates are equally high performance as the MPLS and VPLS scenarios. Check out the two-Catalyst 6500 configurations we deployed for this test.
Download “A Comprehensive Testing of Cisco Systems Catalyst 6500 Sup2T” report here.
For many years, networks have been oversubscribed. Such oversubscription was tolerable in enterprise networks as the applications were not bandwidth intensive, but not anymore. In a datacenter, the primary reason for this oversubscription is insufficient uplink bandwidth from each rack. Each top-of-rack switch is typically connected to two aggregation switches for redundancy. However, half the uplinks are blocked by spanning tree to avoid loops in the network; this reduces the available bandwidth between the rack and aggregation layer of the network by 50%. Arista’s Multi-Chassis Link Aggregation (MLAG) feature removes this bottleneck and allows the utilization of all interconnects.
To learn how, download this paper from Arista Networks.