It depends If the volume would have one dataset on it, like my SPOOL Volumes, then they are very small
If like in my TSO Pool there are lots of tiny (15 track or less) then I make them huge. So it all depends on What the intent of the volume is (1 dataset vs Many Datasets) What size the volume is (Mod3/9/27/54/EAV) You will see an error message when the VTOC or VTOIX is too small. Hope this helps Lizette -----Original Message----- From: IBM Mainframe Discussion List <IBM-MAIN@LISTSERV.UA.EDU> On Behalf Of Peter Sent: Saturday, July 4, 2020 10:12 AM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Vtoc and index sizing based on Mods Hello Group Apology for being ignorant. Is there a formula or any constraints for initialising a specific dasd Mod ? How do arrive to a specific vtoc and index value while initialising a dasd ? Please help me to understand Peter ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN