NEC Storage Software PathManager, User Manual

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Chapter 3 Functions of NEC Storage PathManager
C:\>spscmd -getmscsmode
MSCS : Disable
C:\>spscmd -setmscsmode E
C:\>spscmd -getmscsmode
MSCS : Enable
C:\>
The -getmode option of the spscmd can also be used to check the settings for MSCS liaison.
C:\>spscmd -getmode
Class : Enterprise
Failback : Active
MSCS : Disable
C:\>
Note also that the settings for dynamic load balancing cannot be made if the program is working
with MSCS.
3.5 Path patrol
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This function periodically monitors the state of all paths that are available or unavailable for use. NEC
Storage PathManager has a health check function and a recovery check function. In the health check function,
paths that are available for use are monitored, and the failover function is automatically activated in case of
failures. In the recovery check function, paths that are not used due to failures are monitored, and the
failback function is automatically activated at the time of failure recovery. The path patrol service and the
NEC Storage PathManager driver allow execution of these functions.
The path patrol service issues requests for path monitoring to the NEC Storage PathManager driver every
specified period of time. Once the NEC Storage PathManager driver receives requests, it checks the state of
specified paths. The NEC Storage PathManager driver issues monitoring I/O if the paths have not been used
for a certain period of time. When the I/O is successfully complete, the paths are regarded as being available
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