Introduction; Troubleshooting Overview; Network Time Protocol - Brocade Communications Systems StoreFabric SN6500B Troubleshooting Manual

Introduction

In this chapter

Troubleshooting overview

This book is a companion guide to be used in conjunction with the Fabric OS Administrator's Guide.
Although it provides a lot of common troubleshooting tips and techniques, it does not teach
troubleshooting methodology.
Troubleshooting should begin at the center of the SAN - the fabric. Because switches are located
between the hosts and storage devices and have visibility into both sides of the storage network,
starting with them can help narrow the search path. After eliminating the possibility of a fault within
the fabric, see if the problem is on the storage side or the host side, and continue a more detailed
diagnosis from there. Using this approach can quickly pinpoint and isolate problems.
For example, if a host cannot detect a storage device, run the switchShow command to determine if
the storage device is logically connected to the switch. If not, focus first on the switch directly
connecting to storage. Use your vendor-supplied storage diagnostic tools to better understand why
it is not visible to the switch. If the storage can be detected by the switch, and the host still cannot
detect the storage device, then there is still a problem between the host and switch.

Network time protocol

One of the most frustrating parts of troubleshooting is trying to synchronize switch's message logs
and portlogs with other switches in the fabric. If you do not have NTP set up on your switches, then
trying to synchronize log files to track a problem is more difficult.
Fabric OS Troubleshooting and Diagnostics Guide
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Troubleshooting overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
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Most common problem areas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
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Questions for common symptoms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
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Gathering information for your switch support provider . . . . . . . . . . . . . . . . . 5
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Building a case for your switch support provider . . . . . . . . . . . . . . . . . . . . . . 7
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