RSPAN
Remote Switch Port Analyzer or RSPAN is a type of SPAN that is used on Cisco switches that allows you to copy all traffic from a single or multiple source ports or source VLANs to a destination interface that is on a different switch. This is in contrast to SPAN which copies traffic to a destination interface on the same switch.
When using RSPAN you must to use a dedicated VLAN for your RSPAN traffic so that traffic can travel from the source switch to the destination switch.
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