Like media modules installed in the ONline System Concentrator, the EMM is assigned to a network on the concentrator backplane. The configuration and
If you have modules assigned to different Ethernet networks in a concentrator, you should use multiple EMMs to track statistics on the individual networks. For configuration management, however, only one EMM in the concentrator can be the master EMM - all other EMMs are considered slaves.
A slave EMM can collect statistics and listen to traffic on the network to which it is assigned. Since the slave does not have control of the Control Bus, it cannot configure modules or detect faults. The slave module will take over as master if the master EMM fails, thus providing fault tolerance for your concentrator management. The administrator assigns a mastership priority level between 1 and 10 to each EMM.
Since all EMMs are factory set with a priority level 10, the first EMM you install will automatically become the master for that concentrator. All other EMMs you install should have their mastership priority changed to a lower value so as not to conflict with the first EMM.
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