Users Guide
Figure 37. Normal Operating FRRP Topology
A virtual LAN (VLAN) is congured on all node ports in the ring. All ring ports must be members of the Member VLAN and the Control
VLAN.
The Member VLAN is the VLAN used to transmit data as described earlier.
The Control VLAN is used to perform the health checks on the ring. The Control VLAN can always pass through all ports in the ring,
including the secondary port of the Master node.
Ring Status
The ring failure notication and the ring status checks provide two ways to ensure the ring remains up and active in the event of a switch
or port failure.
Ring Checking
At specied intervals, the Master node sends a ring health frame (RHF) through the ring. If the ring is complete, the frame is received on
its secondary port and the Master node resets its fail-period timer and continues normal operation.
If the Master node does not receive the RHF before the fail-period timer expires (a congurable timer), the Master node moves from the
Normal state to the Ring-Fault state and unblocks its Secondary port. The Master node also clears its forwarding table and sends a control
frame to all other nodes, instructing them to also clear their forwarding tables. Immediately after clearing its forwarding table, each node
starts learning the new topology.
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Force10 Resilient Ring Protocol (FRRP)