Managing Multipath I/O For Devices; Understanding Multipathing; What Is Multipathing - Novell LINUX ENTERPRISE SERVER 10 - STORAGE ADMINISTRATION GUIDE 7-2007 Administration Manual

Managing Multipath I/O for
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Devices
This section describes how to manage failover and path load balancing for multiple paths between
the servers and block storage devices.
Section 5.1, "Understanding Multipathing," on page 43
Section 5.2, "Multipath Management Tools," on page 44
Section 5.3, "Supported Storage Subsystems," on page 46
Section 5.4, "Configuring the System for Multipathing," on page 47
Section 5.5, "Adding multipathd to the Boot Sequence," on page 49
Section 5.6, "Enabling and Starting Multipath I/O Services," on page 49
Section 5.7, "Adding Support for the Storage Subsystem to /etc/multipath.conf," on page 50
Section 5.8, "Configuring User-Friendly Names in /etc/multipath.conf," on page 50
Section 5.9, "Tuning the Failover for Specific Host Bus Adapters," on page 51
Section 5.10, "Configuring Multipath I/O for the Root Device," on page 51
Section 5.11, "Configuring Multipath I/O for an Existing Software RAID," on page 52
Section 5.12, "Using Multipathed Devices," on page 53
Section 5.13, "Viewing Multipath I/O Status," on page 54
Section 5.14, "Scanning for New Devices without Rebooting," on page 55
Section 5.15, "Managing I/O in Error Situations," on page 56
Section 5.16, "Resolving Stalled I/O," on page 57
Section 5.17, "Additional Information," on page 57
Section 5.18, "What's Next," on page 57

5.1 Understanding Multipathing

Section 5.1.1, "What Is Multipathing?," on page 43
Section 5.1.2, "Benefits of Multipathing," on page 44
Section 5.1.3, "Guidelines for Multipathing," on page 44

5.1.1 What Is Multipathing?

Multipathing is the ability of a server to communicate with the same physical or logical block
storage device across multiple physical paths between the host bus adapters in the server and the
storage controllers for the device, typically in Fibre Channel (FC) or iSCSI SAN environments. You
can also achieve multiple connections with direct attached storage when multiple channels are
available.

Managing Multipath I/O for Devices

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