Date:         Thu, 17 Feb 2000 12:12:50 -0600
Reply-To:     MP WELCH <MP.WELCH@MAIL.SPRINT.COM>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         MP WELCH <MP.WELCH@MAIL.SPRINT.COM>
Subject:      Re: Copying SAS Datasets safely
Comments: To: TWB2@PGE.COM
Content-Type: multipart/mixed;

Tim Berryhill writes:

>At least in V6, it is perfectly safe to copy or
>move SAS libraries with OS utilities.

Unfortunately, there are potential issues when using OS
Utilities to backup/restore SAS V6 Libraries under MVS
SAS V6.

---

SAS TECH notes mention a few potential problems including:

Backup considerations for V6 multivolume disk format SAS data libraries
SAS NOTE -- V6-SYS.SASIO-7929
SAS Version 6 disk format multivolume libraries are unique data
structures
in that they are actually comprised of up to five separate physical data
sets, each residing on a separate volume, cataloged under the same DSN.
The fact that the logical SAS data library structure is comprised of
multiple physical MVS data sets means that a separate DSCB is maintained
for each data set. A side effect from having multiple physical data sets
is that the format 1 DSCB DS1IND80 bit, which indicates whether the
volume
the data set resides on is the last volume, is on for each data set
comprising the library. This fact presents problems for backup
operations
and utilities that support sequential access methods. The utilities
honor the DS1IND80 bit setting and make it impossible to back up the
logical library as a single data set. Manual intervention is required
to ensure the library is backed up in volume sequence order, and access
to the library data sets should be restricted to read only to ensure
data integrity.

Possible reasons for having a truncated SAS data library
SAS NOTE -- V6-SYS.SASIO-C142
DF/dss backup with TOLERATE(ENQFAILURE) while the library
is allocated DISP=OLD to a SAS task(batch job, interactive
session, SAS/SHARE)

Message associated with a Failed Open due to truncation
SAS NOTE -- V6-SYS.SASIO-C141
ERROR: Library TEST appears to have been truncated. The internal
       library structure reflects a high formatted relative block
       number that is greater than the number of blocks actually in
       the MVS dataset. This may be the result of using non-SAS
       utilities to copy a library into a dataset with insufficient
       space or to copy a library with an imbedded EOF mark. This
       library will not be opened.

Misplaced EOF marker copying Version 6 libraries with FDR
SAS NOTE -- V6-SYS.SASIO-4230
An embedded end-of-file marker may be placed in a SAS data library
if the library is moved to unlike devices using FDR. The problem
will occur on the movement of SAS data libraries from 3380 to 3390
devices if the data library on the 3380 was created with a
blocksize ranging from 1/2 track(23476) to 1/5 track(9076). Subsequent
processing of the SAS data library may result in USER315 abends
and the following error message: ERROR: PHYSICAL I/O ERROR ON
SAS DATA LIBRARY. The associated SYNDAF error message may include
the text END OF FILE

---
Diana,

You may want to check with Tech Support to determine if you may
have an issue with your OS Utility and the integrity of your
SAS datasets.

mp welch