User manual

iSCSI GbE to SAS/SATA II RAID Subsystem
88
User Manual
3. Here are the objects, a Source VD and a Target VD. Before starting clone process, it
needs to deploy the VD Clone rule first. Click the “Configuration” button.
4. There are three clone configurations, describe on the following.
x Snapshot space:
This setting is the ratio of source VD and snapshot space. The default ratio is 2 to 1. It
means when the clone process is starting, the system will automatically use the free RG
space to create a snapshot space which capacity is double the source VD.
x Threshold: (Become effective after enabling schedule clone)
The threshold setting will monitor the usage amount of snapshot space. When the used
snapshot space achieves its threshold, system will automatically take a clone snapshot
and start VD clone process. The purpose of threshold could prevent the incremental copy
fail immediately when running out of snapshot space.
For example, the default threshold is 50%, the system will check the snapshot space
every hour, when the snapshot space used over 50%, and the system will automatically
sync the source VD and target VD. Next time, when the rest snapshot space has been
used 50%, in other words, the total snapshot space has been used 75%, and the system
will sync the source VD and target VD again.