Dell EqualLogic PS6210XS EqualLogic Group Manager Administrator s Guide PS Ser - Page 29

Figure 4. PS Series Group Table 5. PS Series Group Callout 1 Description PS Series group Storage area network (SAN) comprising one or more PS Series arrays connected to an IP network. Arrays are high-performance (physical) block storage devices. 2 PS Series members One or more PS Series arrays represented as individual members within a pool to which it provides storage space to utilize. 3 PS Series storage pools Containers for storage resources (disk space, processing power, and network bandwidth). A pool can have one or more members assigned to it. A group can provide both block and file access to storage data. Access to block-level storage requires direct iSCSI access to PS Series arrays (iSCSI initiator). Access to file storage requires the FS Series NAS appliance using NFS or SMB protocols and the Dell FluidFS scale-out file system. With storage data management features, you can: • Manage a group through several built-in mechanisms such as ssh, serial line, telnet, and web-based user interfaces. You do not need an external management station or management software. • Configure the system to alert you to management activity or problems through log files, SNMP traps, and email notification • Add more arrays (up to 16) to a group to increase capacity and performance • Secure data and management access with authorization and authentication mechanisms • Protect storage data with replication and snapshots How Groups Work Each group member cooperates with other members to automate resource provisioning and performance optimization. The storage system partitions the RAID-protected disk space that each member contributes to the storage pool into fixed-sized chunks of data, called pages. Pages logically separate the volume presented to the hosts from the physical resources of the storage array. Each volume has a page map that allocates pages to the members. The system automatically load balances data by performing transactional operations that move pages across member's disks and across all members in a pool. When a group receives a client server request, it identifies the location of the data and transfers the request to the member or members that contain the data. As capacity and performance requirements increase, you can expand a group. When you add an array to an existing group, more space is immediately available. New members learn configuration and performance information from the group. You can also retire older equipment from the group as needed. You can choose a member to remove, and it will automatically offload its data to other Architecture Fundamentals 29