We ran an IDCAMS BACKUP to disk for a large file and it ABENDed with the message 0P86I

Document ID : KB000051618
Last Modified Date : 14/02/2018
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When running a new IDCAMS backup of a RRDS file under Dynam/D comtrol, the BACKUP failed with "0P86I REQUEST FOR I/O BEYOND EXTENT LIMITS. The file is 42 tracks in size and the catalog entry has a primary of 15 cyl and 3 secondary, so we shouldn't be running out of space.

If I take Dynam out of the JCL and run with out to an open disk it works fine.


Because IDCAMS does not use standard I/O routines (LIOCS or logical IOCS) but uses it's own physical IO routines instead, the dynamic LUB allocation routines Dynam uses to select an available SYSnnn from the system conflicts with IDCAMS. To prevent the conflict, and allow Dynam to use the SYS numbers IDCAMS has pre-determined, we recommend setting "Prohibit Dynamic LUB Allocation:" to YES (the default is NO) on screen CAYD-2120 for the dataset in question. The 'P' DLBL option may also be used.


Note that it is also necessary to pre-assign the file, using either a // ASSGN SYS005,...... or DYNOPEN ;

... ... ... ... ... ... ..

The following note is from the CA Dynam User Guide (7.1);

Pre-Open Processing-DYNOPEN

The DYNOPEN utility program lets you pre-open a disk data set. It performs basic CA Dynam/D and Catalog Management services for files that are to be processed by other utility programs (such as IBM's DITTO or IDCAMS utilities). It also supports programs that do not issue opens when restarting from checkpoint.

These other utility programs access the label information and validate the logical unit assignment of files to be processed before the files are actually opened. DITTO and IDCAMS require the use of DYNOPEN. Without the use of DYNOPEN, these types of programs can cancel because CA Dynam/D has not been invoked to perform its open processing.

DYNOPEN provides the following services:

  • Dynamic creation of label information
  • Disk pool management
  • Automatic Volume Recognition and Assignment (AVR)

DYNOPEN can also be used to resolve labels for the IBM SORT product, SM2. SM2 performs pre-open checking of volume serial number and extents for input files, which is not compatible with CA Dynam/D catalog-controlled files, POOL volume serial numbers, and AVR facilities, unless DYNOPEN is used. Pre-open processing is performed by a dummy open call to CA Dynam/D. Therefore, all CA Dynam/D processing is done for a file before the next OPEN input statement is read.

See the User Guide for additional details on the use of Dynam D with IDCAMS, LIBR and other non-standard utilities.