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108Chapter 4: EIU maintenance
A simple form of load balancing is used such that multiple
For more information on EIU redundancy and sparing, refer to “EIU sparing and redundancy” on page 39.
Figure 25 shows the EIU redundant configuration.
Figure 25 EIU redundant configuration
Subnet 1 Subnet 2
CM
EIU 9
FP
AP
ELIU
EIU 1
EIU 2
EIU 3
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EIU 3 advertises CM, EIU 9, FP, AP and ELIU
IP address every 30 sec-
External router
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Can be another subnet or new network on this side of external router
Can be another subnet or new network on this side of external router
Subnet 2
Automated system maintenance
The EIU hardware is automatically maintained using a variety of techniques common to all DMS products. These techniques fall into the following categories:
•checks on hardware integrity during normal operations (that is, parity or error detection and correction on memory arrays, cyclic redundancy checks [CRC] on data in transit, and erroneous state detection). These