VTS does wonders for HSM. Others have made good points about having all of the backup copies on disk. One other thing that I would like to point out would be the increase in CPU consumption and elapsed time. With tape, the compression is done within the tape controller. If you are backing up to disk, HSM must do the compression. That will significantly increase the CPU and will probably elongate the elapsed time. If you do go with disk, I would highly recommend using zEDC for the compression. That will actually decrease the CPU and improve the elapsed time because the compression ratio is so good and the data is compressed by DSS before being passed to HSM.
Cloud Tape Connector is not an option for HSM data. CTC works on SMS tape data sets, of which HSM and OAM data are not. As noted earlier in this same thread, HSM stacks the data on tape as a single tape file and internally manages the location of each logical data set on tape by storing the File Block ID. CTC doesn't work with this type of setup. Regarding Cloud Storage, HSM and DS8K recently announced support for Transparent Cloud Tiering where the DS8K directly writes migration data to cloud storage. The storage can either be on prem or off prem. The value being that the data no longer flows through the z server, significantly reducing the CPU requirements and eliminating RECYCLE processing. But, backup support is not yet available. For those concerned about the data going to 'the cloud', we expect most z data to go to an on prem cloud, which is within the walls of your existing environments. When going to an off prem cloud, z/OS will be providing data set level encryption, so that the data is encrypted on z before being sent out. By policy, data will be able to be sent to ML2, on prem cloud or an off prem (public or private) cloud. Additionally, IBM announced limited support for this same cloud support to target an IBM VTS. This enables direct data movement between an IBM DS8K and IBM VTS for HSM migration and recall processing, also enabling significant CPU reduction, elimination of 16K block writes and elimination of RECYCLE processing. Glenn Wilcock DFSMShsm Architect ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
