Cisco Cisco MDS 9000 I O Accelerator 정보 가이드
Q&A
© 2009 Cisco Systems, Inc. All rights reserved. This document is Cisco Public Information.
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An engine is bound to only one cluster.
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IOA flow: A tuple of initiator and target that is accelerated within an IOA cluster
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Each flow can perform write acceleration or tape acceleration, or both.
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Each flow is identified by the port world wide name (PWWN) and VSAN ID: (initiator PWWN, target
PWWN, VSAN ID); for example, (I1, T1, V1) identifies a flow.
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IOA flow group: A set of IOA flows classified for a given purpose, such as a tape backup flow group, EMC
Symmetrix Replication Data Facility (SRDF) flow group, and Tivoli Storage Manager (TSM) tape flow group
Q.
Can the same IOA engine handle both tape backup and disk replication flows?
A.
Yes. The same engine can perform both disk and tape write acceleration. In addition, a flow can perform tape
backup or disk replication write acceleration.
Q.
What does IOA’s Service-Oriented Architecture mean?
A.
IOA can be deployed as a service anywhere in the SAN. This is accomplished by using a Cisco developed
technology called FC-Redirect. After IOA is configured, the IOA flows are automatically redirected to an IOA
engine by FC-Redirect no matter where the IOA engine is located. As long as FC-Redirect is available on the
switch connected to the backup server or storage array replication port, the IOA engine can accelerate the
flows.
Q.
What is FC-Redirect?
A.
FC-Redirect is a distributed flow redirection mechanism that can enable redirection of a set of traffic flows to a
special engine that performs services such as IOA and storage media encryption (SME). FC-Redirect is
supported on all Cisco MDS 9500 Series Multilayer Directors and 9200 Series Multilayer Switches since Cisco
MDS 9000 SAN-OS Software Release 3.0.
Q.
Do IOA clusters span fabrics? Do I need separate clusters for fabric A and fabric B?
A.
IOA clusters do not span fabrics. Separate clusters are needed for fabric A and fabric B.
Q.
What are the deployment considerations for IOA?
A.
You need to consider the following criteria when deploying IOA:
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Location of the IOA engine
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Number of IOA engines required
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Hardware options
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ISL capacity of the links connecting the IOA engines
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Number of IOA clusters needed
Q.
Although IOA can be placed anywhere in the SAN, what is the best place for the IOA engine?
A.
The best place for the IOA engine is the core, which has WAN connectivity, for the following reasons:
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Easy planning and transition: Capacity can be planned based on WAN ISL throughput on the same switch.
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Optimal routing: Flows always traverse core switches to reach the remote site.
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Consolidation and scalability: Consolidation reduces the number of engines (and hence the number of
switches) required. Without consolidation, more IOA switches may be required. Only four IOA switches per
cluster are supported.
Special considerations for IOA engines hosted on multiple core switches (in a single fabric) are:
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The core switches should be interconnected to provide the best possible redundancy.
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The connecting ISLs should have at least the same capacity as the aggregate MAN or WAN link connecting
the two sites to help ensure that the ISLs can carry the traffic in case of an IOA engine failure.