Dell AX4-5 Hardware Installation Guide - Page 12

EMC® PowerPath® Limitations in a Direct-Attached Cluster, SAN-Attached Cluster, PowerPath - san performance

Page 12 highlights

Figure 1-1. Direct-Attached, Single-Cluster Configuration cluster node public network private network cluster node Fibre Channel connections Fibre Channel connections storage system EMC® PowerPath® Limitations in a Direct-Attached Cluster EMC PowerPath provides failover capabilities and multiple path detection as well as dynamic load balancing between multiple ports on the same storage processor. However, direct-attached clusters supported by Dell connect to a single port on each storage processor in the storage system. Because of the single port limitation, PowerPath can provide only failover protection, not load balancing, in a direct-attached configuration. SAN-Attached Cluster In a SAN-attached cluster, all of the nodes are attached to a single storage system or to multiple storage systems through a SAN using redundant switch fabrics. SAN-attached clusters are superior to direct-attached clusters in configuration flexibility, expandability, and performance. Figure 1-2 shows a SAN-attached cluster. 12 Introduction

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12
Introduction
Figure 1-1.
Direct-Attached, Single-Cluster Configuration
EMC
®
PowerPath
®
Limitations in a Direct-Attached Cluster
EMC PowerPath provides failover capabilities and multiple path detection as
well as dynamic load balancing between multiple ports on the same storage
processor. However, direct-attached clusters supported by Dell connect to a
single port on each storage processor in the storage system. Because of the
single port limitation, PowerPath can provide only failover protection, not
load balancing, in a direct-attached configuration.
SAN-Attached Cluster
In a SAN-attached cluster, all of the nodes are attached to a single storage
system or to multiple storage systems through a SAN using redundant switch
fabrics. SAN-attached clusters are superior to direct-attached clusters in
configuration flexibility, expandability, and performance.
Figure 1-2 shows a SAN-attached cluster.
cluster node
private network
public network
cluster node
storage system
Fibre Channel
connections
Fibre Channel
connections