Backup and recovery management: know your data and your storage
Backup and recovery continues to be an important but perplexing part in an otherwise solid data management and protection plan. The usual suspects include growing data loads, nonexistent backup windows, too much network traffic or poor performance, inefficient storage hardware, media management problems and poor backup reporting.
An assessment of your storage environment and backup systems is the first step in establishing and clarifying effective polices and procedures for managing data. Policy-based tools to manage storage resources are gaining in popularity and usability. This category can include information lifecycle management, compliance with data retention regulations, assigning certain applications performance priority, assigning certain departments access priority, and other operational goals to be met.
Lifecycle utilities are frequently seen as an efficient complement to applications such as e-mail or database programs in order to evaluate and match the frequency of accessing data to proper storage so that older data can be identified before it becomes oppressive to manage. Looking at data to view how the age of the files can be categorized (such as 0 to 30 days, 31 to 90 days, and 91 days or older) may help in making smart decisions about what data is eligible for archiving or even deleting.
Grooming or vetting data prior to backup will reduce the backup load. Tape storage, for example. For most enterprises where tapes are regularly taken off site for archiving purposes, the data may be staged first to a disk system in a present-day equivalent of hierarchical storage management. Disk storage allows fast and easy recovery for frequently accessed files in the case of accidental data loss. In the case of data that need not be as frequently accessed, depending on the acceptable recovery time, manual tape retrieval may be perfectly reasonable for most operations. This data can be removed from onsite disk storage and archived on tape with little sacrifice in efficiency and a realistic timeframe for recovery.
When data management is happily married to storage, and current technologies are meeting your needs, maintaining harmony is still an ongoing challenge. In most cases, a storage environment will consist of SAN, NAS, DAS and backup resources, as well as critical 24x7 application servers like DNS servers and SQL servers, all working separately and in concert, inter- and intra-departmentally, core-to-edge and end-to-end-so it becomes more important to be able to perform efficient, dynamic monitoring and maintenance of as many or as few points as are likely to be taxed.
For enterprises using a SAN, continual monitoring of the network's health is a priority for the best degree of data availability, backup success and restorability. A downed switch or a pulled-out cable will assuredly prevent a proper backup from being carried out. There are several effective management applications either pre-packaged with SAN hardware or available separately that can provide local views of the network topology to troubleshoot and even provide analysis and reports. However, you may or may not be able to integrate these with other reporting tools you rely on, and they may not be thorough enough to include switch I/O trending, asset management, alerting and notification, as well as performance monitoring.
Application monitoring should be considered an essential part of storage management. In the case of DNS, when a critical DNS server goes down, the quicker the problem is identified and corrected, the sooner data can be made available-meaning less financial loss is incurred and less recovery time may be required later. Similarly, monitoring SQL or Exchange resources reduces total backup and recovery costs by eliminating application downtime, grooming data and even finding poorly allocated space.
Monitoring NAS filers as well as any accessible DAS will also allow file analysis, trend reporting, and capacity planning to assure a longer life and better availability to reduce operational expenses and assure simpler recovery.
