030311 Machine Alert for 2097/2098

• Document number:

  030311

• Machine type:

  2097/2098

• Models affected:

  All models at Driver 79

• Abstract:

  Nondisruptive Coupling Facility Dump support available for z10 machines.

Description

MCL009 in the N24403 (CFCC) stream has been released to provide microcode changes to support nondisruptive Coupling Facility (CFCC) dumps on z10 machines at DR79. This MCL can be installed nondisruptively however, a reactivate of the CF partition(s) will be required to fully activate this level of code. This MCL was released to RETAIN on February 28, 2011 in Bundle #42. Once activated you will be running with CFCC Release 16 / Service Level 4.01.

This support was delivered as part of a comprehensive diagnostic package delivered with z196 and available now on z10. The overall goal of this package is to provide a reasonably coherent, concurrent snapshot of data across multiple sysplex members, exactly when problems are detected within the Coupling Facility or the connectivity with the attached sysplex members. These dumps can be initiated by System Z firmware or by z/OS(with supporting APAR's). The types of problems that could automatically trigger these dumps are:
- Inconsistent lock data detected between Coupling Facilities.
- Link time-outs
- Duplex structures out of sync (break duplex)

Additional information:
In order to provide for the additional storage requirements to capture the dumps, Coupling Facility Control Code(CFCC) will require an additional 250 MB of storage on top of what CFCC is using today. Typically on a z10 EC machine today, CFCC code will utilize approximately 100MB out of the total storage defined to the image. After MCL009 is installed and activated, this number will grow to approximately 350MB in total.
Note: Failure to define enough storage to the CFCC image after this MCL is installed, will prevent the CFCC image from activating, or could even prevent the customer from allocating structures in the Coupling Facility, due to insufficient storage.

Due to the internal control block changes needed to support these diagnostics, as well as the additional storage requirements noted above, this MCL will require a re-activate of the CFCC image(s).

This code change does NOT increase or affect structure sizes, however you should consider the increase in storage requirements as a result of the new CFCC code when planning structure size requirements.

In addition to the MCL, the following new function software APAR's are required to utilize this new function:
z10 - APAR OA33723 (z/OS Version 1 / Rel. 9 and above)
z196 - APAR OA31387 (z/OS Version 1 / Rel. 10 and above).

Recommended Action

Product Engineering recommends the following before installing this MCL:

If you do not have Coupling Facility images defined on your z10 processor, no actions required.

For those customers who do have Coupling Facility images defined on z10 processors, you should review the need to perform a 'CF reactivation' with your customer as well as the additional storage requirements noted above prior to the installation of MCL009.

For those customers who choose to defer re-activation of the Coupling Facility image(s), you can install the MCL and the code will be marked as PENDING. The CFCC storage size changes would be picked up during the next Power-On-Reset or CFCC image activation. We strongly recommend you review these additional storage requirements with the customer prior to installing the MCL and make any image profile adjustments in advance.

VM environments that run Virtual CF guests, should also plan accordingly for the re-activate and storage size increase.


Please contact your next level of support if you have any questions or require guidance related to this notification.