Cisco Systems manual SN 5428-2 Cluster Management Overview, Interface Naming, 1-25

Chapter 1 Before Configuring SN 5428-2 Storage Router Software

SN 5428-2 Cluster Management Overview

SN 5428-2 Cluster Management Overview

You can configure Cisco SN 5428-2 Storage Routers in a cluster to allow the storage routers to back each other up in case of failure.

Note A storage router can participate in a cluster only if it is deployed for SCSI routing.

An SN 5428-2 Storage Router can be configured in a cluster with one other SN 5428-2, or with an SN 5428, connected as follows:

•Connected to the same hosts

•Connected to the same storage systems

•Connected to each other through their management and high availability (HA) interfaces

In a cluster, storage routers continually exchange HA information to propagate configuration data to each other and to detect failures in the cluster. The storage routers exchange HA information through two separate networks: one connected to the management interface of each storage router and the other connected to the HA interface of each storage router. To make sure that HA information is exchanged reliably between storage routers, the storage routers balance the transmission of HA information between the management and the HA interfaces.

A storage router cluster supports up to 12 active instances of SCSI routing. For example, if one storage router is already running two instances, it is eligible to run up to ten additional instances. At any given time, an instance of SCSI routing can run on only one storage router in a cluster. The instance continues running on the storage router where it was started until one of the following actions occurs:

•The instance is explicitly stopped or failed over to the other storage router in the cluster.

•The instance automatically fails over to another storage router because an interface is unavailable or another software or hardware problem occurs. This automatic fail over uses intelligent eligibility guidelines to determine fail over.

See Chapter 10, “Configuring a High Availability Cluster,” for more information about configuring a high availability cluster.

Interface Naming

Configuring the SN 5428-2 Storage Router software requires that you understand hardware interface naming. This section describes the interface naming system used with the SN 5428-2 Storage Router hardware.

Each storage router interface is assigned a three-character name consisting of two lower-case letters followed by a number. The letters designate the interface type; the number designates the chassis slot occupied by the interface (See Figure 1-23).

Cisco SN 5428-2 Storage Router Software Configuration Guide

OL-4691-01 1-25