HP Surestore Disk Array FC60 HP SureStore E Disk Array FC60 - (English) Advanc - Page 75

Topology and Array Planning Storage Capacity For configurations where maximum storage capacity at minimum cost is a requirement, consider configuring the disk array in RAID 5 (using the maximum number of data drives per parity drives) and only supplying one or two hot spare drives per disk array. Also, purchase the lowest cost/Mbyte drive available (typically the largest capacity drives available at the time of purchase). This configuration allows the maximum volume of storage at the lowest cost. Disk arrays configured in this way will need to be carefully monitored to make sure that failed disks are promptly replaced. Expanding Storage Capacity The disk array is designed to meet a range of capacity requirements. It can be configured with up to six disk enclosures, and from 4 to 60 disk modules. The disk array can be purchased with enough capacity to meet your current storage requirements. As your storage needs grow, you can easily add more capacity to the Disk Array FC60. There are several ways to increase the storage capacity of the disk array. It can be increased by replacing existing smaller capacity disk modules with larger capacity disk modules, by adding more disk modules to the disk enclosures, or by adding additional disk enclosures. The best method for expansion is to install all six disk enclosures at initial installation (fullbus configuration). Then, install only the required capacity (number of disk modules), leaving empty disk slots for future expansion. Additional disk modules can be installed as the requirement for additional capacity grows. This method allows for greater flexibility in LUN creation and does not require that the system be shut down for expansion. Adding disk enclosures to the array after initial installation requires that the system be shut down during the installation. All the remaining configuration expansion methods require that the data to the array be suspended (the system shut down) to add additional disk enclosure storage to the array. Note For maximum performance, all six SCSI channels from the controller enclosure must be connected with a minimum of two disk modules per channel (disk enclosure configured for full bus mode). To expand a split-bus configuration (adding more disk enclosures) will require shutting the host system down. If the initial installation included only one or two disk enclosures, then Array Design Considerations 75