Home > Storage > PowerMax and VMAX > Mainframe > Dell PowerMax: Data Protector for z Systems (zDP) Best Practices > Overview
Customers can use SnapVX and zDP to support traditional disaster recovery (DR) testing at the DR site which formerly used full volume copies (clones or BCV). Ideally, the DR test should not affect the rolling protection of zDP during the test. A linked snapshot for the DR test consumes space as the snapshot ages. You should determine how long a DR test snapshot needs to live to accurately plan the space consumption.
There are multiple reasons why the DR site array can be used for short-interval SnapVX zDP cyber protection. You can IPL (for testing purposes) the entire set of volumes in your DR test LPARs. Also, the consequences of an array SRP reaching unsafe operational levels are much lower if the snapshots are in the SRDF distance array. SRDF replication protection may be at risk, but host outages that are due to the SRP being 100% full are impossible if the snapshots are in the distance array.
You can create SnapVX snapshots and zDP snapsets in remote arrays that are connected by SRDF by using a local instance of Mainframe Enablers software that is running on a z/OS LPAR. TimeFinder SnapVX can communicate with the remote array. The RMT (remote) parameter with CREATE, LINK, UNLINK, and TERMINATE functions enable controlling snapshots on the remote array.
With zDP, when the VDG and TGT constructs are created at the local (production) site using Mainframe Enablers, use the MODIFY command to ADD devices and populate the VDG or TGT. Using the RMT(GP) parameter in the MODIFY, ADD device list allows you to create zDP snapsets at the array that is attached to the remote array in SRDF group GP (in the example above). This configuration method is deployed when there is no active z/OS LPAR running at the DR site.
The host-performance impact that is mentioned in Deploying local-array SnapVX and zDP does not apply if the SRDF replication method is synchronous. If the replication is synchronous mode, this configuration causes a host-performance impact (ECA enabled) if you create a consistent snapshot of an SRDF R2 group. If the replication method is SRDF/Asynchronous, ECA is not required, and the host impact at the production site is negligible.