Hi Peter, On the issue of confusion in respect of model DSCBs and SMS, my question would be "Why bother to set up a model DSCB."
Over three decades ago it was realised that a generic model data set could be used instead of a model DSCB, so many installations defined such a generic data set, i.e. SYS1.MODSCB, with zero track allocation. The advantage of this method at the time was that it avoided VTOC pollution, as volumes where much smaller and hence so were VTOC sizes. Model DSCB creation could generate VTOC full conditions even when there were large amounts of free space on the volume. The disadvantage is that whilst the catalogue data set name had to be coded on the DD statement, so did the other DCB parameters to override those of the model data set. This lead to coding like: // DCB=(SYS1.MODSCB,LRECL=80,RECFM=FB,BLKSIZE=3600) With modern disks and larger VTOCs the VTOC pollution is less likely to occur unless people are creating large numbers of small data sets, so I guess actual model DSCBs are more viable, and could theoretically reduce the number of parameters on the DD statement if there were a model or pattern explicitly created for each GDG with the appropriate DCB attributes. If this is a valid reason then it mitigates the use of SMS DATACLAS In preference I believe. The discussion on how to create a model or patter DSCB is on Page 499 of the z/OS SMS Using Data Sets manual. Kind regards - Terry Terry Sambrooks Director KMS-IT Limited 228 Abbeydale Road South Dore Sheffield S17 3LA UK Tel: +44 (0)114 262 0933 WEB: www.legac-e.co.uk Reg: England & Wales 3767263 at the above address All outgoing E-mails are scanned but it remains the recipients responsibility to ensure that their system is protected from viruses, trojans, worms, and spy-ware. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
