Friday, March 16, 2012

Red Alert : Potential data loss when executing data recovery in a DB2 10 (NFM) Data Sharing environment

Here's a new Red Alert:

PTF UK76697 (APAR PM51093) is required for DB2 10 for z/OS NFM (New Function Mode) customers executing data recovery in a Data Sharing environment

Description:

IBM has become aware of potential data loss when executing data recovery in a DB2 10 Data Sharing environment.

The problem is related to Fast Log Apply processing when LRSN values are used for log record sequencing and may result in some log records not being processed when duplicate LRSN values are encountered. This situation applies to the RECOVER and RESTORE SYSTEM utilities and LPL and GRECP recovery. The REORG utility and DB2 restart processing are not exposed to this issue.

Possible symptoms include ABEND04E RC00C90102 DSNIBHRE:0C22 accompanied by MSGDSNI012I PAGE LOGICALLY BROKEN or other consistency errors during log apply. Other abends or errors may be encountered following log apply processing, including errors reported by CHECK INDEX or CHECK DATA.

Customers may validate their data by using CHECK INDEX or CHECK DATA utilities and any issues should be reported to IBM Software Support to determine root cause.

Recommended Actions:

It is recommended that all DB2 10 for z/OS data sharing customers apply PTF UK76697 as soon as possible. Customers planning to migrate to DB2 10 NFM should ensure that UK76697 is applied before they do so. The corrective maintenance can be applied incrementally across members of a data sharing group. A group wide restart is not required.

Fast Log Apply processing may be disabled to prevent further exposure to this problem before UK76697 can be applied. The process for doing so is as follows, and should be repeated for each subsystem:

  1. Edit macro DSN6SPRC in the SDSNMACS library.
  2. Change &SPRMFLB SETC '10' to &SPRMFLB SETC '0'.
  3. Run job DSNTIJUZ to reassemble and relink the new zparm.
  4. Recycle DB2 to load the new zparm.

Refer to the cover letter for UK76697 for further details regarding this issue.


If you want to have an overview of all past Red Alerts, then take a look over here. You can also subscribe on that same page so you'll be notified of any future Red Alert.

Thursday, March 15, 2012

CA Technologies Reference Guide for DB2 10 for z/OS is out

Yesterday I received the following mail :
"Now is the time to order your CA DB2 10 Reference Guide.

The cost of printing and shipping has gone up dramatically due to the size of the latest version of the guide, so you can order them, but they will cost about 15 Euro.

We will give away free guides to those who register here: http://www.ca.com/gb/lpg/forms/emea/fy12/uk/mf/91122_90307.aspx

First come, first serve. We have about 50 to give away for free, so reserve yours TODAY!!!

Good luck"
I don't think any further comment is needed on this one. Even if you can't get it for free, I'm sure it's worth every cent you have to pay for it. And if you wonder : what the h*** is he talking about, just follow the link. And if you're not convinced by now, know that some call it The Source of True Wisdom !

Tuesday, March 13, 2012

A new z/OS release every 2 years !

This morning I posted about a statement of direction about changing the pace of releases of z/OS. Well, since then, I've been receiving some more information about this.

There will indeed be a new release every 2 years from now on. So, the next release will be in the second half of 2013. Some other interesting bits of information :
  • IBM intends to keep the N-2 compatibility so that customers can still migrate 1 or 2 releases forward. This means you might choose to only migrate every 4 years.
  • In order to support this scheme, the support for currently available releases (z/OS 1.12 and z/OS 1.13) will be adjusted in order to allow clients to bridge to the new release cycle.
  • z/OSMF releases should also be following the same release pattern.
  • Selected features may become available in between releases through e.g. SPE's

Well, that's it for now. And you know the drill : as long as it's not officially announced, IBM might still change things. More info should become available within the next 60 days.

A new z/OS release every 2 year ?

I won't pretend to be the first to publish about this, because I just read it in Cheryl Watsons List which I received this morning. If you don't receive it yet, you can find the content over here.
So Jeff Magdall, z/OS program leader from IBM, held the MVS Program Opening and Keynote at Share yesterday. Don't go looking for the presentation, it's over here, but for the moment, there's just a title slide.

So, what's it about ? I'll quote Cheryl's list :
"Today at SHARE, Jeff Magdall, z/OS Program Leader from IBM, described an upcoming SOD (Statement of Direction) for z/OS. Starting with z/OS 1.13, z/OS releases will now be available every other year instead of every year. That means that the next release of z/OS will be the second half of 2013 (not September 2012, as expected). I think this is terrific news for our customers! IBM has found that only 5% of z/OS customers migrate every year, while the great majority of customers migrate every other year or so".
So what could the release scheme look like then ?

TO AVOID ANY CONFUSION I REMOVED THE GRAPH + MOST OF THE COMMENTS ON IT AS IT WAS DEFINITELY NOT CORRECT

(...)
If, I say, if EOS dates should move up one year, perhaps some customers will have their releases longer supported or they might save some money by avoiding Lifecycle Extension Support on their current release.

As soon as anything official comes out, I'll definitely share all the details with you.

Thursday, March 8, 2012

Red Alert : Possible data loss for EAV Users on releases z/OS 1.11, 1.12 and 1.13

Here's a new Red Alert:

Possible data loss for EAV Users on releases z/OS 1.11, 1.12 and 1.13 using DSS Logical Dump or HSM Migrate and Backup processing

Description:

DSS may skip some of the user's data set during dump processing and result in a failure when attempting to Restore, Recall or Recover these data sets. This failure will prevent any of the data set from being restored. The problem can occur when using EAV volumes with data sets in the EAS region (Extended Addressability Space - cylinder managed region) where the addresses of the data set extents are not in ascending cylinder order, ie. the CCCH address of a later extent is less than a previous extent.

Please see APAR OA38942 for additional information and actions to determine exposure.

Recommended Actions:
Apply ++APAR for OA38942

If you want to have an overview of all past Red Alerts, then take a look over here. You can also subscribe on that same page so you'll be notified of any future Red Alert.