Computer Associates BABWBR1151S38 Implementation Guide - Page 17

Data Transfer Requirements Network and Computer Infrastructure Requirements If you have not already done so, you should familiarize yourself with the hardware, network, and site configuration that your backup and recovery plan supports. You should know: ■ The numbers and types of computers and workstations you need to back up. ■ The identities of computers that have media libraries or devices attached (these are the CA ARCserve Backup servers). ■ The type of SCSI or fiber cabling connecting each library to its server and the transfer rate of the cabling. ■ The type of library on each server. ■ The type of devices in each library and their transfer rate. ■ The degree of data compression that you plan to use, if any. ■ The types and capacities of your network, subnets, routers, and so on. Data Transfer Requirements The overall data transfer rate for your backup and recovery system sets the amount of time required for storage operations. You have to balance your backup window, backup data, and recovery speed requirements against the capabilities of your existing infrastructure and the budgetary constraints of your organization. After you have quantified the amount of data that you have and the times when you can back it up, you can roughly estimate the minimum data transfer rate that you must achieve to fully back up the data in the allotted time. Use this requirement as a starting point for the decisions you make later in this section. To calculate a rough, minimum transfer rate, divide the amount of data by the amount of time available to back up the data: databackedup ÷ backup_window = required_rate Example: Data Transfer Calculation If you have 1 Terabyte to back up and 5 hours available each night and you intend to back up everything in one session, you need to achieve a rate of 200 GB per hour. Chapter 2: Planning Storage Environments 17