IIn a system employing GDS Snapshot, backups can be created using snapshots from proxy volumes during the services operation.
However, to secure consistency of snapshot data, the services must be stopped temporarily when creating a snapshot (when parting a proxy volume from a master volume).
See
For details on snapshots by synchronization, see "1.5.1 Snapshot by Synchronization."
For securing consistency of snapshot data, see "3.17 Ensuring Consistency of Snapshot Data."
Figure 7.48 Backup Schedule
Note
Instant Restore
If an error occurs in master volume data while the master volume and a proxy volume are joined, the same error occurs in data of the proxy volume and instant restore becomes unavailable. If this happens, you must restore data from tape. After you execute online backup by parting a proxy volume, you are recommended to leave the proxy volume parted until just before re-executing online backup.
Note
Snapshot through Disk Unit's Copy Functions
If groups are hierarchized, or if proxies are in mirroring configuration with the multiplicity of two and higher, copy functions of disk units are unavailable for copying data from masters to proxies. For details, see "A.8 Using Advanced Copy Function in Proxy Configuration" and "3.19 Using Dell EMC TimeFinder or Dell EMC SRDF in Proxy Configuration."
Note
When Using Dell EMC TimeFinder or Dell EMC SRDF
In the procedures described below, volumes are used for snapshot operations. However, when using TimeFinder or SRDF, use groups for similar operations.
When using TimeFinder, if standard devices that compose the master group and BCV devices that compose the proxy group are established, cancel the BCV pairs prior to joining the master and the proxy.
When using SRDF, have source (R1) devices that compose the master group and target (R2) devices that compose the proxy group split prior to joining the master and the proxy.
After relating the master and the proxy, do not perform TimeFinder or SRDF operations for BCV pairs or SRDF pairs that compose the master and proxy using the SYMCLI command and so on before canceling the relation.
Note
Snapshot by Synchronization Use Conditions
See the following sections for points of concern.
Information
Use Conditions for Copy Functions of Disk Units
See "A.8 Using Advanced Copy Function in Proxy Configuration" and "3.19 Using Dell EMC TimeFinder or Dell EMC SRDF in Proxy Configuration."
