Library Table of Contents Index Previous Page (Alt-p) Next Page (Alt-n) Comments

Connecting to multiple loops of disk shelves

Requirements for connecting additional loops  Top

Before you connect multiple loops of disk shelves, make sure that your storage appliance meets the following requirements:

Connecting multiple loops to a storage appliance  Top

Each additional loop requires an FC-AL disk adapter in the storage appliance. See the System Configuration Guide at http://now.netapp.com for information about adapters supported by your storage appliance. The following illustration shows a storage appliance connected to two loops of DS14 disk shelves without the benefit of multipath cabling.

To connect another loop of disk shelves to a storage appliance, complete the following steps.

Step

Action
1

If...

Then

Your single filer has four FC-AL adapters with single copper interfaces

Connect the loop to the remaining pair of FC-AL adapters on the filer by following the procedure in Connecting a disk shelf to a storage appliance.

Your storage appliance has a dual optical interface
  1. Follow Step 1 through Step 6 of the procedure in Connecting a disk shelf to a storage appliance.
  2. Connect the storage appliance to LRC/ESH B of disk shelf 1 in the next loop of disk shelves. See Ensuring data integrity with multiple loops which tabulates possible cabling options.
  3. Go to Step 8 of the procedure in Connecting a disk shelf to a storage appliance.

Ensuring data integrity with multiple loops  Top

Software enhancements provided by Data ONTAP 6.1 or later enable you to ensure data integrity and incorporate redundancy through the use of multipath cabling in your filer system.

FC-AL adapters with the copper interface

Each loop of disk shelves must be connected to two FC-AL adapters.

The following table shows the possible configuration for a filer with four adapters connected to two loops of shelves.

Number of loops

Number of copper interface adapters

1

2

3

4

1

LRC A

X

-

-

-

LRC B

-

-

-

X

2

LRC A

-

-

X

-

LRC B

-

X

-

-

The following illustration shows a filer with two copper FC-AL adapters connected to a single loop of DS14 disk shelves with the benefit of multipath cabling.

FC-AL adapters with the dual optical interface

If Port A (Port 1) of the adapter is connected to the LRC/ESH A of disk shelf 1 of a particular loop, Port B (Port 2) of the same adapter is not connected to LRC/ESH B of disk shelf 1 of the same loop. This is done in order to insure maximum redundancy at the FC-AL Host Bus adapter level. The following table shows the possible configuration for a storage appliance with two adapters connected to two loops of shelves.

Number of loops

Number of dual optical interface adapters

1

2

A

B

A

B

1

LRC/ESH A

X

-

-

-

LRC/ESH B

-

-

-

X

2

LRC/ESH A

-

-

X

-

LRC/ESH B

-

X

-

-

The following illustration shows a filer with two dual optical FC-AL adapters connected to two loops of DS14 disk shelves with LRC modules that have the benefit of multipath cabling.

The following table shows a possible configuration for a filer with three adapters connected to three loops of DS14/DS14mk2 FC disk shelves.

Number of loops

Number of dual optical interface adapters

1

2

3

A

B

A

B

A

B

1

LRC/ESH A

X

-

-

-

-

-

LRC/ESH B

-

-

-

X

-

-

2

LRC/ESH A

-

-

X

-

-

-

LRC/ESH B

-

-

-

-

-

X

3

LRC/ESH A

-

-

-

-

X

-

LRC/ESH B

-

X

-

-

-

-

The following table shows the possible configuration for a filer with four adapters connected to four loops of DS14/DS14mk2 FC disk shelves.

Number of loops

Number of dual optical interface adapters

1

2

3

4

A

B

A

B

A

B

A

B

1

LRC/ESH A

X

-

-

-

-

-

-

-

LRC/ESH B

-

-

-

X

-

-

-

-

2

LRC/ESH A

-

-

X

-

-

-

-

-

LRC/ESH B

-

-

-

-

-

X

-

-

3

LRC/ESH A

-

-

-

-

X

-

-

-

LRC/ESH B

-

-

-

-

-

-

-

X

4

LRC/ESH A

-

-

-

-

-

-

X

-

LRC/ESH B

-

X

-

-

-

-

-

-

Library Table of Contents Index Previous Page (Alt-p) Next Page (Alt-n) Comments

Copyright © 1994-2003, Network Appliance, Inc. All rights reserved.
Part No. 210-00592
File: cabling5.htm
Last updated: 12/03/03 13:48:53