Clustering; Hardware Requirements; Software Requirements - Cisco MDS 9000 series Configuration Manual

1 Overview
S e n d d o c u m e n t a t i o n c o m m e n t s t o m d s f e e d b a c k - d o c @ c i s c o . c o m
You can have more than one IOA service engine in the same site in the IOA cluster. In fact, this is the
Note
preferred configuration wherein if an IOA service engine fails , then all the flows bound to it can be
automatically moved to another available IOA service engine in the same site. This is taken care of by
the IOA cluster based load balancer.

Clustering

IOA is offered as a clustered service that consists of a set of switches that operates in coordination with
each other. Clustering provides the following advantages:
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IOA clustering uses standard algorithms to provide consistency and reliability of the configuration
metadata required for the service to be operational. A master switch is internally elected by the clustering
infrastructure to perform certain tasks such as load-balancing and failover. To keep the process simple,
we recommend that you provision the IOA from the master switch. If the network fails, which partitions
the switches in a cluster, a standard majority node-based quorum algorithm is used to decide which
partition should be operational to be able to guarantee the consistency.
An internal node ID that is allocated as a part of adding the switches to the cluster is used in the master
election algorithm. If you intend to manage IOA from a specific switch or a site, we recommend that you
use this switch as a seed switch when a IOA cluster is configured, and also add all the nodes in this site
before you add the nodes from the remote site into the IOA cluster.

Hardware Requirements

IOA is supported on the Cisco MDS 9000 Family 18/4-port Multiservice (MSM-18/4) Module, the Cisco
MDS 9222i Switch, and the 16-Port Storage Services Node (SSN-16) module. Each MSM-18/4 Module
and 9222i Switch has one service engine that can be configured for the Cisco IOA service. The SSN-16
module has four service engines that can be used for the IOA service.

Software Requirements

To enable IOA feature on the MSM-18/4 Module or SSN-16 Module, the MDS 9000 Family switch must
run Cisco NX-OS Release 4.2(1) or later. You must also use Fabric Manager 4.2(1) to manage the
switches. Hosts must be connected to a switch running Cisco SAN-OS 3.3(1c) or later. Targets must be
connected to a switch running Cisco NX-OS Release 4.2(1) or later.
OL-20708-01, Cisco MDS NX-OS Release 5.0(1a)
Single point management— IOA can be managed as a fabric service from a single switch. You need
not configure multiple switches individually to provide IOA as a fabric service.
Automatic load-balancing— You can provision all of the flows that need to be accelerated through
IOA. Clustering allows these flows to load-balance automatically across all the available IOA
service engines within the cluster. It also makes it easy to plan for capacity as you just need to add
an additional IOA service engine when there is a need to add more throughput within IOA.
Resiliency— Allows automatic failover of the IOA flows whenever an IOA service engine fails on
any of the switches. If a switch fails, an alternate switch in the cluster takes over the failed flows to
maintain the contiuity of the IOA service.
Cisco MDS 9000 Family I/O Accelerator Configuration Guide
Clustering
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