Protecting Microsoft Exchange Server in SMBs.
Few SMBs can afford to be specialists in the backup process or the inner workings of Exchange Server. Yet they must be able to accurately restore an Exchange Server without undue effort. Many businesses also need to be able to retrieve e-mail messages in order to comply with the Sarbanes-Oxley Act, the Health Insurance Portability and Accountability Act of 1996 (HIPAA), and other regulatory guidelines.
The first step an SMB should take is to develop a backup strategy for their Exchange Server, with an eye toward automating the backup process for quick and easy backups and precise restores. Automated technology can eliminate inefficient manual oversight and allow IT staff to devote their time to other tasks.
Developing a Backup Strategy for Exchange Server
When developing a backup strategy for Exchange Server, there are five important areas to consider:
* Scope: What kind of information do you need to protect? How much granularity do you require in your restores?
* Latency: How much lag time can you afford before updated data is transferred to backup media?
* Redundancy: Can you create multiple sets of backup media to protect your data?
* Retention: Do you need to retain data for a minimum amount of time or delete outdated e-mails on a regular basis to save space?
* Administration: Can the backup strategy be easily set up and maintained? Can both backups and restores be automated?
Protecting a computer running Exchange Server presents unique challenges. In addition to protecting the integrity of the Exchange Server e-mail databases, SMBs must consider other factors. For example, can the backup strategy protect the operating system and application settings on the computer that is running Exchange Server? Is it sufficient to restore the entire Exchange database or is a finer granularity required? Can an individual mailbox or contact be restored without the expense, effort, and inconvenience of retrieving the entire database?
If latency increases, the threat of losing data also increases. Each company needs to determine how much latency is acceptable for its particular circumstances. A commonly employed strategy to reduce latency is to perform daily incremental backups and weekly full backups. Because running backups at peak times can cause network slowdowns that affect worker productivity, it is best to perform backups at night when traffic is typically lower.
Selecting the right type of backup to perform during each session (full, incremental, or log/incremental) and permitting backups of Exchange Server while the application is live and in use also reduces latency.
Multiple sets of backup media used in conjunction with an onsite/offsite rotation strategy provide a high level of protection. Having more than one set of backup media protects against backup media failure. Keeping one set of media in a secure offsite location protects against disasters that might damage or destroy onsite data.
Organizing media into Backup Sets, which are assigned a name and can be easily tracked for subsequent backups and restores, makes media rotation simpler for an SMB with limited skill. Many of the backup and restore products available today use fairly complex media rotation strategies to track and update tapes as they are rotated offsite and onsite. The relationship between the various tapes must be carefully tracked in order to locate the data necessary for a restore of the Exchange Server application or a mailbox to a particular point in time. For example, the commonly used grandfather-father-son strategy requires a minimum of 9 tapes that must be used in a precise order. To make matters worse, these backup tapes are typically tracked with pencil, paper, and a calendar.
Many companies want a backup strategy that retains e-mail messages for a minimum amount of time, but then purges the messages after a set time has passed in order to save storage space. If Exchange Server backups are planned carefully, an e-mail retention policy can be easily achieved by storing Exchange Server data in a series of dated backups and recycling older backup media that contain the data to be purged.
Backup Sets make it easy to institute a policy to delete outdated e-mail files. For example, a corporation might have a policy that e-mail must be retained for at least 60 days and at most 90 days. This policy can be implemented with three Backup Sets, each of which is used for a month. After the third month, the Backup Sets contain 90 days of backup data. The first set of media can be reused, which deletes the first 30 days of data and leaves 60 days of data in the Exchange Server backup media.
Typically, IT staff handle a multitude of varying tasks and cannot afford to be specialists in the backup and restore process or in the inner workings of Exchange Server. Under these circumstances, backups must be fast, restores must be accurate, and these tasks must not demand excessive amounts of management or effort.
Backing Up Exchange Server
The innovative technology behind Dantz Retrospect backup and restore software allows SMBs with little or no IT staff to easily back up Exchange Server with full confidence. Retrospect's features make it easy to increase scope, reduce latency, and implement redundancy and retention policies.
Complete protection for the Exchange Server can only be achieved by a three-tier process.
At the highest level, protect the server that hosts the Exchange Server application. Back up all valuable operating system settings and create a disaster recovery CD to boot the server if it is non-functional. (Most backup software requires backup administrators to create disaster recovery CDs regularly, before disaster occurs, whether they are needed or not. In these cases, IT staff must create a new disaster recovery CD whenever changes occur in the hardware or setting configurations. This process demands considerable time and attention from the backup administrator and makes it difficult to maintain a consistent disaster recovery strategy. Instead, SMBs should look for a program that will create a bootable DR disc for a dead server from a recent backup, when and if it is needed.)
The next level of protection is for the Exchange Server application itself. Full, incremental, and log/incremental backups protect the Exchange Server database as well as the application settings for Exchange Server. An agent specifically designed for Microsoft Exchange Server APIs ensures completely consistent backups and restores. With an Exchange agent (usually an add-on or option), protecting the Exchange Server is straightforward because the computers running Exchange Server, the Exchange Server Storage Groups, and individual mailboxes automatically show up in a source selection window along with other computers and volumes on the network, making it easy to select them for backup.
The deepest level of protection is at the mailbox level. Mailbox-level backups should only take new and changed e-mail messages during each backup session. It should be easy to locate and restore an individual e-mail message, appointment, or contact, as well as restore a single mailbox without restoring the entire application.
Restoring an Exchange Server
Restores of Exchange servers are notoriously difficult without a backup software package that offers Exchange support. IT staff are usually required to understand the inner workings of Exchange Server or to know exactly when and how the Exchange Server application needs to be disabled and enabled during the restore process.
Restoring involves a multistep process that must be completed in a particular order:
* Identify the databases on the backup media
* Disable the Exchange Server computer's roll forward option
* Restore the backup data from the full backup and the required incremental/differential backups in the correct order
* Enable the roll forward option
* Restore the logs
Because backups are usually spread over many pieces of backup media, the location of the content may not automatically be tracked, and multiple restore operations must be performed on the Exchange Server application itself.
To simplify restores, a Database Tracking Controller included in an Exchange-specific backup tool easily tracks every full, incremental, and log backup performed, so it can display the history of backups or create a list of the exact media required to restore Exchange Server to a given point in time.
The three-tiered backup approach makes it possible to restore the computer that is hosting Exchange Server as well as the Exchange Server application itself, individual mailboxes, or even a single e-mail message. One of the main reasons why SMBs back up their Exchange Server application is to perform mailbox-level restores. These kinds of restores usually involve restoring one or two specific items quickly when users need them in a business emergency. Mailbox-level restores allow for rapid recovery if an important piece of e-mail (for example, a message with a revised business contract as an attachment) was deleted inadvertently.
However, this specific control over restores exceeds the capabilities of the built-in backup that comes with Exchange Server. The built-in backup utility does not automate the restore process by tracking the contents of the backup media or controlling the Exchange Server during restores, and does not allow for mailbox-level restores.
Most backup and restore software for Microsoft Exchange Server requires extensive expertise and effort to set up and maintain, but companies that do not have extensive staffs highly trained in backup procedures or the complex inner working of Exchange Server are often lost. A complete backup strategy for Exchange requires attention to scope, latency, redundancy, retention, and administrative concerns. It involves protecting the computer hosting Exchange Server, the Exchange Server storage groups, databases, and individual mailboxes as well as tracking all backups and uses that information to automatically execute the precise procedures needed to restore Exchange Server without requiring extensive manual intervention.
Don Chouinard is the director of product management at Dantz Development Corp. (Walnut Creek, CA)
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|Title Annotation:||Disaster Recovery & Backup/Restore; small and midsize businesses|
|Publication:||Computer Technology Review|
|Date:||Jan 1, 2005|
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