IBM FlashSystem 900, Installation And Maintenance Manual

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External Wrap Testing Parallel Channel Adapters
Note: This procedure requires a channel- trained IBM service representative or
customer's channel- trained person.
This section explains the basic concepts for preparing the channels for testing,
contains rules governing channel attachment, and provides procedures for
preparing the wrap blocks. When you are certain about your configuration, follow
the procedures in this section.
Attention:
¹
Do not unplug the cables unless all the device addresses that are attached to
the channel have been varied offline.
¹
Do not remove the cables unless necessary. Removing and reattaching bus
and tag cables can cause pins to bend.
¹
Run diagnostic option 2 with a wrap block when:
1. You are installing a Parallel Channel Adapter as an upgrade
2. There is still an indication of a Parallel Channel Adapter channel error and
you have already run diagnostic option 1 and it ran cleanly.
Concepts
When testing the Parallel Channel Adapters with wrap blocks, follow the procedures
to ensure that all channels affected by your test remain operational.
1. First trace the V-cables and the Channel Interface Cables from the Parallel
Channel Adapters that you are testing to their input and output connectors.
2. Even if you are not testing additional Parallel Channel Adapters in the
multiaccess enclosure, trace the V-cable attached to the additional adapters to
their input and output connectors.
3. Sketch your configuration, if necessary, to be sure that you know how the
adapters are attached to the channels.
Rules for Parallel Channel Adapter Testing
Prepare the channel cables, other V-cables, and the other Channel Interface
Cables so that the channel can be operational while you are testing the adapter. To
preserve all channels to the host that might be affected by your test, follow these
rules:
1. Be sure to vary the channel offline (make the channel inoperational).
2. When setting up the wrap test maintain a terminated channel path to the host
as shown in Figure 3-4 on page 3-24 and Figure 3-5 on page 3-25.
3. If you want the channel to be online while doing wrap tests, vary the channel
online after preparing the wrap test connections.
4. Perform the wrap tests that you need to perform.
5. Reconnect your cables according to the sketch that you made.
Chapter 3. Multiaccess Enclosure Problem Determination
3-23