Source

RETAIN tip: H194143

Symptom

At certain levels of ESM firmware, an issue exists which keeps problematic devices from being taken out of the Fibre Channel (FC) loop.

Because these failing devices are allowed to remain on the loop, additional devices may be adversely affected, potentially causing the good devices to be kept from inserting into the loop.

In this scenario, access to data may be impacted.

Affected configurations

The system may be any of the following IBM servers:

• DS4200 Storage Server, type 1814, any model
• DS4300 (FAStT600) Dual Controller and Turbo Storage Server, type 1722, any model
• DS4400 (FAStT700) Storage Server, type 1742, any model
• DS4500 (FAStT900) Storage Server, type 1742, any model
• DS4700 Storage Server, type 1814, any model
• DS4800 Storage Server, type 1815, any model

The system is configured with one or more of the following IBM Options:

• DS4000 EXP420 Storage Enclosure, type 1812
• DS4000 EXP710 Storage Enclosure, type 1740
• DS4000 EXP810 Storage Enclosure, type 1812

The ESM firmware for the EXP 810/710/420 is affected.

This tip is not operating system specific.

Solution

A fix for this issue (commonly referred to as Bad Zone Recovery) is available in the following ESM firmware levels:

• EXP 810/420: 98B5
• EXP 710: 9681

It is highly recommended that your ESM firmware minimally be at the above levels or preferably, at the latest levels available from IBM.

Additional information

The fix in the above levels of ESM firmware is designed to use Port Test Before Insert (PTBI) to test and reinsert drives into a FC loop if there has been an extended link down.

This should allow all devices, other than the problematic device(s), to reengage in the loop.