Supported Platforms
Understanding Link Aggregation in an EX8200 Virtual Chassis
An EX8200 Virtual Chassis is typically used to aggregate standalone EX8200 switches at the distribution layer into a Virtual Chassis. The advantages of connecting multiple EX8200 switches into a Virtual Chassis include better managed bandwidth at a network layer, simplified configuration and maintenance because multiple devices can be managed as a single device, and a simplified Layer 2 network topology that minimizes or eliminates the need for loop prevention protocols such as Spanning Tree Protocol (STP).
You can extend the benefits of a network using an EX8200 Virtual Chassis at the distribution layer by configuring the network connections of the devices connecting to the EX8200 Virtual Chassis as link aggregation group (LAG) bundles. A LAG balances traffic across the member links within an aggregated Ethernet bundle and effectively increases the uplink bandwidth of network traffic into the Virtual Chassis. An EX8200 Virtual Chassis can support up to 239 LAGs and up to 12 interfaces per LAG. Member links of a single LAG can span between multiple switches that are part of the same EX8200 Virtual Chassis.
Configuring LAGs into the Virtual Chassis minimizes the need for spanning-tree protocols by bundling multiple interfaces into a single interface. Another advantage of link aggregation is increased link availability compared to that of links not configured in LAGs. Because the LAG is composed of multiple member links, the LAG continues to carry traffic over the remaining links when a link fails.
Link aggregation is also useful for combining Virtual Chassis Ports (VCPs) within an EX8200 Virtual Chassis. See Understanding Virtual Chassis Port Link Aggregation in an EX8200 Virtual Chassis.
