Dell EqualLogic PS6210XS EqualLogic Group Manager Administrator s Guide PS Ser - Page 34

Callout 7 8 9 10 Description Space received from PS Series arrays to allocate data as needed through various structures (volumes, snapshots, thin provisioning, replicas, containers, SMB/NFS, quotas, and local users and groups). Volumes Storage allocated by a PS Series group as addressable iSCSI targets. Collection A set of volumes. Snapshots A point-in-time copy of data on a volume. Snapshots can be taken on a single volume or on a collection. Thin-provisioned volume With thin provisioning, a minimal amount of space (10 percent by default) is reserved on a volume and then allocated when the space is needed. For each volume, the group generates an iSCSI target name, which you cannot modify. An iSCSI target name includes a prefix, a string, and the volume name. Initiators use the target name to connect to a volume. For example: iqn.2001-05.com.equallogic:7-8b0900-6d0000000-001ebbc5d80sf0k0-db3 In this example: prefix is string is volume name is iqn.2001-05.com.equallogic 7-8b0900-6d0000000-001ebbc5d80sf0k0 db3 Each volume appears on the network as an iSCSI target. Hosts with iSCSI initiators use the volume's target name to connect to the volume. Each iSCSI volume supports a set of features and capabilities: • Snapshots - To protect volume data from mistakes, viruses, or database corruption, you can use snapshots. • Replication - To protect against disasters, you can replicate volume data from one group to another. • Thin Provisioning - To manage storage capacity utilization on demand, you can use thin provisioning. • Clones - To create a master or boot image, full system backup, or transfer a system to another person, you can use cloning. • Volume Unmap (block reclaim) - To recover space previously allocated to volumes, you can unmap them. • Volume Undelete - To restore mistakenly deleted volumes, you might be able to use volume undelete. NOTE: The system permanently deletes volumes after 7 days, and sometimes sooner if the space is needed. • Volume Folders - To organize volumes into folders for quick visual reference, you can use volume folders. Using folders has no effect on the contents of the volumes. • Control Access to iSCSI Initiators - To protect your volumes from unauthorized and uncoordinated access by iSCSI initiators, you can use access control policies. • Control Access to Hosts (servers) - To prevent inadvertent corruption of the volume caused by multiple hosts writing to it in an uncoordinated manner, enable multihost access to a volume. Volume Attributes You set some attributes when you create a volume; other attributes use default values. In most cases, you can modify all the volume attributes. Template volumes and thin clones have some restrictions. 34 Architecture Fundamentals