HiDRO backups; tape blocksize.

Products

• VM:Backup for z/VM
• VM:Backup High-Speed Disaster Recovery Option (HiDRO)

Issue/Introduction

How do I determine what tape blocksize my Hidro backups are using?   I am writing to IBM 3592 E05 units in a 3494 tape library.

Environment

Release: VMBKUH00400-2.8-VM:Backup-HiDRO (VM:Backup HiDRO)
Component:

Resolution

. 
HiDRO blocks its records at 65280 so the blocksize for all backups is 65280, regardless of what tape media you are writing to.   Similarly, VM:Backup creates a blksize of 65535. 
So, basically, both are 64K records in length.