Concept Guide
Member VLAN Spanning Two Rings Connected by One Switch
A member VLAN can span two rings interconnected by a common switch, in a gure-eight style topology.
A switch can act as a Master node for one FRRP group and a Transit for another FRRP group, or it can be a Transit node for both rings.
In the following example, FRRP 101 is a ring with its own Control VLAN, and FRRP 202 has its own Control VLAN running on another ring.
A Member VLAN that spans both rings is added as a Member VLAN to both FRRP groups. Switch R3 has two instances of FRRP running
on it: one for each ring. The example topology that follows shows R3 assuming the role of a Transit node for both FRRP 101 and FRRP 202.
Figure 42. Example of Multiple Rings Connected by Single Switch
Important FRRP Points
FRRP provides a convergence time that can generally range between 150ms and 1500ms for Layer 2 networks.
The Master node originates a high-speed frame that circulates around the ring. This frame, appropriately, sets up or breaks down the ring.
• The Master node transmits ring status check frames at specied intervals.
• You can run multiple physical rings on the same switch.
Force10 Resilient Ring Protocol (FRRP)
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