Chapter 3 Functions of NEC Storage PathManager
for use. If the I/O results in an error or if it is not complete before time-out, the paths are regarded as being
unavailable for use.
3.
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5.1
H
H
ealth check
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This function detects failed paths and makes them fail over by periodically issuing monitoring I/O to
available paths that have not been used for a certain period of time. This function is used mainly to monitor
failures in alternative paths in environments except for those in which dynamic load balancing is conducted.
Standby
In use
Failures
Unavailable
Available
Active
Figure 3-7 Failover as a result of health check
3.
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5.2
R
R
ecovery check
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This function detects paths that recovered from failures and makes them fail back by periodically issuing
monitoring I/O to failed paths. This function is used for archiving active failback or standby failback.
Standby
In use
Failures
Unavailabe
Available
Active
Figure 3-8 Failback as a result of recovery check
III-17
Summary of Contents for NEC Storage PathManager 3.1
Page 1: ...NEC Storage Software NEC Storage PathManager User s Manual Windows version IS201 5E ...
Page 4: ......
Page 6: ......
Page 7: ...Part I Overv view P Pa ar rt t I I O Ov ve er rvi ie ew w ...
Page 13: ...Part II Installation P Pa ar rt t I II I I In ns st ta al ll la at ti io on n ...
Page 18: ......
Page 19: ...Part III Functions P Pa ar rt t I II II I F Fu un nc ct ti io on ns s ...
Page 47: ...Part IV Operation P Pa ar rt t I IV V O Op pe er ra at ti io on n ...
Page 58: ......
