Dell PowerConnect B-FCXs, Configuration Manual

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346 PowerConnect B-Series FCX Configuration Guide
53-1002266-01
Metro Ring Protocol (MRP)
10
How ring breaks are detected and healed
Figure 65 shows ring interface states following a link break. MRP quickly heals the ring and
preserves connectivity among the customer networks.
FIGURE 65
Metro ring – ring break
If a break in the ring occurs, MRP heals the ring by changing the states of some of the ring
interfaces:
•
Blocking interface – The Blocking interface on the Master node has a dead timer. If the dead
time expires before the interface receives one of its ring RHPs, the interface changes state to
Preforwarding. Once the secondary interface changes state to Preforwarding:
F
F F
C us tomer A
Switch B
C us tomer A
C us tomer A
C us tomer A
Switch A
Switch C
Switch D
M as ter
Node
F
F
F
F
F
F
F