Formatting a larger than 2.2 TB hard drive on the IBM N2115 SAS controller - IBM System x3630 M4 (7158)

Resolving The Problem

Source

RETAIN tip: H212436

Symptom

In the IBM N2115 configuration interface performing a format on a physical device (hard disk drive), the format job indicates full completion of the task (formatting). However, the SAS controller format process is resident and running. This process is observed by noting the blinking Light Emitting Diode (LED) activity on the hard disks.

(where SAS = Serial Attached SCSI)

Affected configurations

The system can be any of the following IBM servers:

• System x3630 M4, type 7158, any model

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

• IBM N2115 SAS/SATA HBA for IBM System x, option part number 46C8988, any replacement part number

This tip is not software specific.

The Phase 15 firmware for the IBM N2115 controller is affected.

The system has the symptom described above.

Solution

This behavior is corrected in the release of firmware/BIOS version 7.35.01.00 or later levels for the N2115 SAS Controller.

The file is available by selecting the appropriate Product Group, type of System, Product name, Product machine type, and operating system on IBM Support's Fix Central web page, at the following URL:

http://www.ibm.com/support/fixcentral/

Workaround

Not applicable.

Additional information

The issue observed was that for hard disk drives (HDDs) of capacity greater than 2.2 TB, descriptive formatting sense data was being misinterpreted by the controller. The returned sense data was not as expected on one supplier's hard disks. SAS traces were captured and showed that LSI attached to two other supplier hard drives would format as expected. When attached to one supplier's disks, the format would start and the LSI IR utility application would within a few seconds (less than 10 seconds) indicate that it had completed the format task. The disk activity LEDs would remain blinking, indicating a format in process.

If the disk formatting was interrupted, corruption would occur:

The SAS trace data was investigated with the help of development. On the first transaction, the return sense data indicates a 20 in the first block of data. On one supplier hard drive unit, it was found to have data other than 20.

The T10 specification was investigated and found to have content on the return data. The percent complete data in descriptive formatting was specified.

Product Engineering (PE) communicated to LSI that the T10 specification lists that for descriptive formatting that the format percent complete was indicated in the return sense data correctly. Also, Hitachi had a broad compliant implementation, and the controller was not following specifications in reading the percent complete during format.

LSI provided a test debug build. PE verified the fix being implemented with a 3 TB supplier hard drive, and took a SAS trace.

LSI confirmed that a fix put in Phase 15 code stream was the solution. The fix is due to release with the Phase 18 build.