Specifications

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Summary of Best Practices for Storage Area Networks

Key factors to consider are how dynamic is the business’ SAN environment and the

typical degree of urgency for changes.

The business management and SAN administrators will need to determine a schedule

for routine changes (such as new storage allocations or re-zoning operations) deemed

appropriate and prevents the deployment of massive numbers of changes being

implemented in a single maintenance window.

For example: schedule all changes to take place on Saturday morning along with a

requirement that all new requests must be submitted a full week prior to the window

where they will be implemented. Such timing gives the appropriate administrator(s)

sufficient time to develop and review the implementation plan for the change. If

appropriate detailed checklists and plans are developed, reviewed and approved, then

the change will be implemented.

One final change management related topic to be discussed involves proper

documentation of the change and device configurations which were modified. In short,

the configuration documentation for a solution should theoretically be sufficient to re-

create a functionally equivalent copy of the solution, entirely from scratch. Change

Management records should be detailed enough to “roll-back” the current configuration

to any given earlier version. Moreover, the documentation should be detailed enough

that any administrator skilled in the products used should be able to obtain a similar

configuration result as somebody intimately familiar with the solution. Lastly, this

information should be in a form easily read by the administrators and other technical

personnel involved in the solution.

Why is it a best practice to keep these records? Some might argue that the

configuration information for a storage solution is largely “self-documenting.” After all,

most storage devices have ways of obtaining a configuration dump. (Indeed,

maintaining copies of these dumps is part of Best Practices for change tickets.)

However, a report from the storage device on what the configuration is does not leave

an Administrator with any information as to what it should be. A mismatch between the

records and what the device reports can be a useful starting point for troubleshooting

(or better yet, preventing) errors.

Also, a configuration dump may not store the information in a way that makes it useful

to the administrator. For instance, in a SAN environment with multiple storage systems,

it would be very tedious to find which storage system has resources allocated for a

given host. In addition, the configuration interface may completely lack business-related