1. Backing Up Lesson 12

2. Backups A backup is simply a copy of the data on a computer’s hard disks, stored on another medium in case a hard drive fails. If a drive failure occurs, an administrator can repair or replace the drive, and then restore the data from the backup. Whatever disk technologies your servers happen to be using, they are not a replacement for regular backups. Every server that contains valuable data should be backed up on a regular basis, with a copy of the backup stored offsite.

3. Backups A backup solution consists of the following two elements: – One or more backup drives. – A backup software product. A backup strategy specifies what data you will back up, how often you will back it up, and what medium you will use to store the backups. The decisions you make regarding the backup hardware, software, and administrative policies should depend on how much data you have to back up, how much time you have to back it up, and how much protection you want to provide.

4. Storage Device Criteria The three main criteria to consider when evaluating the suitability of a storage device for backups are as follows: – Capacity – Speed – Cost

5. Storage Devices Used for Backups Optical disks Hard disks drives Magnetic tape

6. Tape Library Obviously, a magnetic tape drive array moves you up into an even higher price bracket, but that is still not the ultimate in tape backup technology. To minimize the tape changes you have to make to complete your backups and perform restores, you can purchase an autoloader, sometimes called a tape library. An autoloader is a single device that contains one or more magnetic tape drives, as well as a robotic mechanism that inserts tapes into and removes them from the drives.

7. Drive Interfaces The interface that a backup device uses to connect to a computer is of particular concern to server administrators. No matter how fast the backup device itself, throughput will be slow if the interface cannot deliver data to the drive at a sufficient rate. Magnetic tape drives, in particular, require a consistent stream of data to write to the tape with maximum effectiveness.

8. Drive Interfaces Backup devices can use any of the standard computer interfaces, such as Parallel Advanced Technology Attachment (PATA), Serial ATA (SATA), USB, IEEE 1394, and Small Computer System Interface (SCSI). In most cases, optical drives and internal hard disk drives use PATA or SATA and external hard drives use USB or IEEE 1394. Magnetic tape drives are available that use any of these interfaces, but the vast majority of them use SCSI.

9. Backup Targets One of the most basic functions of a backup software product is to let you select what you want to back up, often called the backup targets. Most backup software programs enable you to select any combination of the following: – Entire servers – Entire disks – Entire volumes – Specific folders – Specific files

10. The Backup Tab

11. Backup Job Types Most backup software products include a collection of standard backup job types that are actually preset filter combinations. The most common of these job types are the following: – Full — Backs up all files to the storage medium and resets their archive bits – Differential — Backs up only the files that have changed since the last full backup and does not reset their archive bits – Incremental — Backs up only the files that have changed since the last full or incremental backup and resets their archive bits

12. Incremental Backups When you run an incremental backup job, you are only backing up the files that have changed since the last backup, whether it was a full backup or an incremental backup. Performing incrementals between your full backups uses the least amount of storage space, but it also lengthens the restore process. If you should have to restore an entire disk, you must first perform a restore from the last full backup, and then you must restore each of the incremental jobs you performed since the last full backup, in the order you performed them.

13. Incremental Backups When restoring from incrementals, the order of the tapes you restore is crucial. You must restore the incrementals in the order they were written, or you might end up with old versions of files overwriting the newer versions.

14. Differential Backups However, because differential jobs do not reset the archive bits on the files they back up, once a file appears in a differential, it appears in every subsequent differential until the next full backup. When you use differential backups, the jobs take a bit longer and they use a bit more storage space, because in some cases you are backing up the same files several days in a row. However, restoring from differentials is simpler and faster, because you have to restore only the last full backup and the most recent differential.

15. Scheduling Jobs All backup products enable you to create a backup job and execute it immediately, but the key to automating a backup routine is being able to schedule jobs to execute unattended. Not all of the backup programs supplied with operating systems or designed for standalone computers support scheduling, but all full- featured backup software products do.

16. Logging Backup Activity As a backup software product feeds data to the drive, it also keeps track of the software’s activities. Most backup software products maintain a log of the backup process as it occurs. You can often specify a level of detail for the log, such as whether it should contain a complete list of every file backed up or just record the major events that occur during the job.

17. Cataloging Files In addition to logging their activities, backup software programs also catalog the files they back up, facilitating the process of restoring files later. The catalog is essentially a database containing a list of every file that the software has backed up during each job. To restore files from the backup medium, you browse through the catalog and select the files, folders, or volumes that you want to restore.

18. Rotating Media One of the most common media rotation schemes is called the Grandfather-Father-Son method. In this method, the terms grandfather, father, and son refer to monthly, weekly, and daily tapes, respectively. – For daily backups, you have one set of “son” tapes that you reuse every week. – For the weekly full backup, you have “father” tapes that you reuse every month. – Then, every month, you perform an additional full backup to tapes in your “grandfather” set, which you reuse every year.

19. Windows Server Backup Windows Server 2008 includes a backup software program that you can use to back up your volumes to an internal or external hard drive, to a writable DVD drive, or to a shared folder on the network.

20. The Windows Server Backup Console

21. System State The system state includes the computer’s boot files, the Windows registry, the COM class registration database, and any system files that are under Windows File Protection. The system state can also include certain role-specific files and databases, if those roles are installed on the computer, such as the Active Directory Domain Services and Active Directory Certificate Services databases, the SYSVOL directory, and the cluster service information. It is also possible to back up the computer’s system state by itself, using the Wbadmin.exe program from the command prompt.

22. The Select Backup Destination Page

23. Performing a Restore Windows Server Backup enables you to restore entire volumes or selected files, folders, and/or applications, using a wizard-based interface in the Windows Server Backup console.

24. Full Server Restore If a disaster occurs in which all of a server’s data is lost, or even just the volumes containing the boot and operating system files, obviously the server cannot start, Windows Server 2008 cannot load, and you cannot run the Windows Server Backup console to perform a restore. It is still possible to perform a full restoration of the server, as long as the backup drive is intact. To perform a full server restore, you must boot the system using a Windows Server 2008 installation disk and access the backup disk using the Windows RE (Recovery Environment) interface.

25. The Install Windows Page

26. Backing UP Active Directory When you perform a scheduled backup of an Active Directory domain controller, or perform a single backup with the Enable system recovery checkbox selected, Windows Server Backup includes the system state as part of the job. The system state includes the Active Directory database, among other things.

27. Non-Authoritative Restore When you open a Command Prompt window in a standard Windows session and restore the system state, you perform a non- authoritative restore. This means that the program will restore the Active Directory database to the exact state it was in at the time of the backup. However, the next time an Active Directory replication occurs, the other domain controllers will update the newly restored system with any changes that have occurred since the backup took place. This means that if you are trying to recover objects that you accidentally deleted, the replication process will cause the system to delete the newly restored objects.

28. Authoritative Restore To restore deleted objects, you must perform an authoritative restore, and to do this, you must restart the computer in Directory Services Restore Mode (DSRM) by pressing F8 during the boot process and selecting the appropriate entry from the Advanced Boot Options menu. After logging on using the Administrator account and the DSRM password specified during the operating system installation, you can perform the system state restore using Wbadmin.exe. Once the restoration of the system state is complete, you can use the Ntdsutil.exe tool to specify the objects that you want restored authoritatively.

29. Backing Up and Restoring Group Policy Objects (GPOs) To back up and restore GPOs, you must use the Group Policy Management console. When you right-click a GPO in the console and select Back Up from the context menu, a Back Up Group Policy Object dialog box appears in which you can specify the location for the backup.

30. Summary A backup is a copy of the data on a computer’s hard disks, stored on another medium in case a hard drive fails. If a drive failure occurs, an administrator can repair or replace the drive and then restore the data from the backup. The three main criteria to consider when evaluating the suitability of a storage device for backups are capacity, speed, and cost.

31. Summary It is possible to use a CD-ROM or DVD-ROM drive for backups. Most servers come equipped with a writable DVD- ROM drive or can easily be retrofitted with one. The drives and media are both relatively inexpensive, and write speeds are reasonably fast.

32. Summary Magnetic tape is the traditional choice for server and network backups. Tape drives are well suited for backups because they are fast, they can hold a lot of data, they can archive that data indefinitely, and their media cost per gigabyte is low.

33. Summary The ever-increasing capacities of hard disk drives, along with their ever-decreasing prices per gigabyte, have led to their use as the primary backup medium for home users and small networks in recent years.

34. Summary Backup devices can use any of the standard computer interfaces, such as Parallel Advanced Technology Attachment (PATA), Serial ATA (SATA), USB, IEEE 1394, and Small Computer System Interface (SCSI). Depending on the type of backup device you select for your servers, a backup software product can be a convenience or an absolute necessity.

35. Summary Most backup software products include a collection of standard backup job types that are actually preset filter combinations. The most common of these job types are full, differential, and incremental. To reuse backup tapes, you must have a carefully planned media rotation scheme so that you don’t inadvertently overwrite a tape you might need later.

36. Summary It is absolutely essential that you perform periodic test restores from your backup tapes or other media to ensure that you can get back any data that is lost. In Windows Server Backup, single backup jobs provide more flexibility than scheduled ones, with the obvious disadvantage that someone must be there to create and start the job.

37. Summary When you create a scheduled backup job, the options are somewhat different from a single, interactive job. When you perform a scheduled backup of an Active Directory domain controller or perform a single backup with the Enable system recovery checkbox selected, Windows Server Backup includes the system state as part of the job.