FUJITSU Storage ETERNUS Multipath Driver V2 User’s Guide for Linux
Copyright 2014 FUJITSU LIMITED
P2U3-0031-15ENZ0
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Chapter 3
Multipath Driver Functions and Operation
This chapter explains various the Multipath Driver functions and how to use the main commands to operate
the functions. The Multipath Driver performs the following functions.
•
Automatic multi-path configuration
When the Multipath Driver is installed, and the storage system is connected to a Linux server, the paths are
automatically configured to perform path failover and load balancing.
•
Failover
If a currently used path fails, the system automatically switches over to another path to access the storage
system, allowing the host application to continue normal operation. The Failover function operates
differently for each storage system model. For details, refer to section
"3.2 Load Balancing/Failover" (page
•
Load balancing
Load balancing (load distribution) is performed on all available paths, improving data performance. The
Load Balancing function operates differently for each storage system model. For details, refer to section
"3.2 Load Balancing/Failover" (page 44)
•
Auto path check
Regular checks are performed on all paths even when they are not being accessed by an application. If an
unusable path is detected, it is disconnected from the system and its status is reported to ETERNUS
Multipath Manager or recorded in the event log.
•
Auto path recovery
Regular checks are also performed on disconnected paths to reconnect those paths that have recovered
from their failure. This function reinforces path redundancy and provides increased reliability.
•
Path disconnection
You can disconnect a specified path by placing it in Offline status. This allows any necessary maintenance
work to be performed. The path can be reconnected after the maintenance.
