Dell Force10 S4820T S4820T Configuration Guide - Page 389

Table 18-1. FRRP Components (continued) Concept Ring Interface State Explanation Each interface (port) that is part of the ring maintains one of four states Ring Protocol Timers Ring Status Ring Health-check Frame (RHF) • Blocking State: Accepts ring protocol packets but blocks data packets. LLDP, FEFD, or other Layer 2 control packets are accepted. Only the master node Secondary port can enter this state. • Pre-Forwarding State: A transition state before moving to the Forward state. Control traffic is forwarded but data traffic is blocked. The Master node Secondary port transitions through this state during ring bring-up. All ports transition through this state when a port comes up. • Forwarding State-Both ring control and data traffic is passed. When the ring is in Normal operation, the Primary port on the Master node and both Primary and Secondary ports on the Transit nodes are in forwarding state. When the ring is broken, all ring ports are in this state. • Disabled State-When the port is disabled or down, or is not on the VLAN. Hello Interval: The interval when ring frames are generated from the Master node's Primary interface (default 500 ms). The Hello interval is configurable in 50 ms increments from 50 ms to 2000 ms. Dead Interval: The interval when data traffic is blocked on a port. The default is 3 times the Hello interval rate. The dead interval is configurable in 50 ms increments from 50 ms to 6000 ms. The state of the FRRP ring. During initialization/configuration, the default ring status is Ring-down (disabled). The Primary and Secondary interfaces, Control VLAN, and Master and Transit node information must be configured for the ring to be up. • Ring-Up: Ring is up and operational • Ring-Down: Ring is broken or not set up Two types of RHFs are generated by the Master node. RHFs never loop the ring because they terminate at the Master node's secondary port. • Hello RHF (HRHF): These frames are processed only on the Master node's Secondary port. The Transit nodes pass the HRHF through the without processing it. An HRHF is sent at every Hello interval. • Topology Change RHF (TCRHF): These frames contains ring status, keepalive, and the Control and Member VLAN hash. It is processed at each node of the ring. TCRHFs are sent out the Master Node's Primary and Secondary interface when the ring is declared in a Failed state with the same sequence number, on any topology change to ensure all Transit nodes receive it. There is no periodic transmission of TCRHFs. The TCRHFs are sent on triggered events of ring failure or ring restoration only. Implementing FRRP • FRRP is media and speed independent. • FRRP is a Dell Force10 proprietary protocol that does not interoperate with any other vendor. • Spanning Tree must be disabled on both Primary and Secondary interfaces before FRRP is enabled. • All ring ports must be Layer 2 ports. This is required for both Master and Transit nodes. • A VLAN configured as control VLAN for a ring cannot be configured as a control or member VLAN for any other ring. Force10 Resilient Ring Protocol (FRRP) | 389