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I need to read large SAS data sets stored on tape in Z/OS that are spread across multiple tapes. I am not in a position to move this data off tape and to store it on our DASD storage on our mainframe.

I am wondering does SAS 9.4 on Z/OS have a limitation to the number of tapes it can utilize when accessing a dataset spread over multiple tapes?

Currently when accessing a SAS dataset that is spread over multiple tapes I declare a libref similar to this:

libname mf v9tape 'mainframe dataset name';

I have been able to successfully read dataset that are spread across multiple tapes this way problem free.

Reading more about the libref statement there is a volser option that I could use the declare which tapes are required, however as per the documentation utilizing this option limits me to utilizing no more than 30 tapes. I am wondering if I do not use this option will SAS apply the 30 tape limit to this statement as it would if I utilized the volser option?

nvlm
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1 Answers1

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I'm not SAS literate, but your question made me curious. z/OS documents that multivolume tape data sets can span over 255 volumes at max (see z/OS DFSMS Using Data Sets, "Maximum Data Set Size", "Maximum Number of Volumes"). So this 30 volume limit is a SAS limit.

Reading the SAS manual (http://support.sas.com/documentation/cdl/en/hosto390/61886/HTML/default/viewer.htm#mvs-stmt-libname.htm) I understand that the volser limit applies when writing a new library, and you want specific volumes to be used. Or, when you want to read a tape library, but the data set is not catalogued, and you therefore need to specify the list of volumes.

Using the volcount you can write to as many as 255 volumes. I conclude that you may read a catalogued tape data set which is spread over as many as 255 volumes.

HTH

phunsoft
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