DELL MD3220 사용자 설명서

Configuration: Device Mapper Multipath for Linux

The MD3200 Series storage array uses a Linux operating system software 

framework, known as Device Mapper (DM), to enable multipath capabilities 

on Linux Host Servers. The DM multipath functionality is provided by a 

combination of drivers and utilities. This chapter describes how to use those 

utilities to complete the process of enabling MD3200 Series storage array on a 

Linux system.
The Device Mapper technology replaces an earlier, proprietary technology, 

known as MPP. MPP was used to enable multipathing for the previous MD 

generation MD3000 Series storage arrays. 

The required Device Mapper software components are installed on a Linux 

host server by running the MD3200 Series Resource media installation program on 

the server, and selecting either the Full or Host install option. For detailed 

installation procedures please refer to the Dell PowerVault MD3200 and MD3220 

storage arrays 

Deployment Guide

. 

Benefits of using DM Multipath include: 

• Detects path failure and re-routes I/O to other available paths
• Revalidates failed paths after path restoration
• Utilizes multiple available paths to maximize performance
• Reconfigures path usage based on path states and error conditions
• Unifies multiple device nodes into a single logical multipath device node
• Indentifies a new multipathed LU and automatically configures a new 

multipath node

• Provides device name persistency for DM devices under /dev/mapper/

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