8.4
Ring redundancy and standby connection
Note
Avoiding bad configurations
When using the commands in this section, you should take particular care because a bad
configuration of this function can have serious negative affects on the network.
Ring redundancy
The ring redundancy function allows several devices to be interconnected in a ring structure.
Since such a topology is not supported in normal network operation, such rings are logically
disconnected using the Media Redundancy Protocol (MRP) or the High Speed Redundancy
Protocol (HRP). If one component fails, all other elements of the ring can still be reached.
The device that logically disconnects the ring is known as the redundancy manager (RM).
The simple structure of the individual MRP rings allows shorter reaction times if disruptions
occur:
● MRP approx. 200 ms
● HRP approx. 300 ms
Complex network topologies cannot be set up with this function.
Standby
Two rings can be connected redundantly in each case via two links (master, slave). This
function is known as the standby connection.
With it, the links of the interfaces of the master device are active and the links of the interfaces
of the slave device are inactive.
Note
Position of master and slave device
The master and slave device of a standby connection (link pair between different structures
of the ring redundancy) must be located in the same ring.
This section describes commands of the ring redundancy function.
Link Check
With the Link Check function, you can monitor the transmission quality of optical sections within
an HRP or MRP ring, identify disturbed connections and under certain conditions turn them
Layer 2 management protocols
8.4 Ring redundancy and standby connection
SCALANCE XB-200/XC-200/XF-200BA/XP-200/XR-300WG Command Line Interface
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