An aggregation layer usually comprises a few blocks of two switches in MCLAG. An aggregation switch is a network device that consolidates traffic from multiple access switches, wireless access points, or other edge devices and forwards it to core switches or routers. By design, it therefore provides resiliency because it will always be deployed in pairs of switches and comes with a recommendation to deploy only dual hot swappable power supplies and redundant fans in each switch to. This design employs a pair of redundant Cisco Nexus 7010 switches on the aggregation and core layers. Virtual device contexts (VDCs) of the Nexus 7000 switches are utilized in the design to create a pair of aggregation VDC switches and a pair of core VDC switches from two Nexus 7010 switches. Each aggregation switch is physically connected to all edge switches and participates in. Switch aggregation, also known as link aggregation or trunking, is a method used in computer networking to combine (aggregate) multiple network connections in parallel.
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