c# print 2d barcode Media Sets in C#.NET

Generation UCC - 12 in C#.NET Media Sets

A media set is a set of one or more tapes or disk files used during a backup. A given media set uses either tape drives or disk drives, but not both. For example, you might stripe a backup operation across a media set of three tapes, one in each of three tape drives. You create a media set by formatting the backup media during a backup operation. To achieve this, in Transact-SQL, use the FORMAT option with the BACKUP DATABASE command. In SSMS, after you choose to back up the database, select the option to back up to a new media set and erase all backup sets. Backups created on a single device constitute a media family.

SQL Server 2005 introduces mirroring of backup media sets by means of the MIR ROR TO option. Mirroring a media set creates a redundant copy of the backup and

increases backup reliability by reducing the impact of any backup device malfunc tions. A mirrored media set includes two to four mirrors, each containing all the volumes of every media family. To ensure proper functioning of a mirrored media set, choose devices that have the same model number from the same manufacturer. Figure 13-2 shows an example of a mirrored media set that consists of two media fam ilies with two mirrors. Each media family contains three media volumes, which are backed up once per mirror.

Corresponding volumes on the mirrors have identical contents, making them inter changeable at restore time. For example, Figure 13-2 shows that the third volume of tape2 is interchangeable with the third volume of tape0. The following example creates the mirrored media set illustrated in Figure 13-2 and backs up the AdventureWorks database to both mirrors:

TO TAPE = '\\.\tape0', TAPE = '\\.\tape1'

MIRROR TO TAPE = '\\.\tape2', TAPE = '\\.\tape3'

FORMAT, MEDIANAME = 'AdventureWorksSet1'

13

1. Which stored procedure can you use to create a logical backup device 2. How do you create a mirrored media set in Transact-SQL

You can back up to a local disk, to a remote disk, or to tape. A media set is a set of tapes or disk files to which backup operations are written. Mirroring a media set by using the MIRROR TO option with the BACKUP DATA BASE statement creates a redundant copy of the backup and increases backup reliability.

You can use the following questions to test your knowledge of the information in Les son 4, Overview of Backup Media. The questions are also available on the compan ion CD if you prefer to review them in electronic form.

Answers to these questions and explanations of why each answer choice is right or wrong are located in the Answers section at the end of the book.

1. In a three-hour window between work shifts every night, you perform a full backup of the Partners database to a locally attached tape drive. Recently, the backups have been taking longer than the three-hour window allows, so you need to reduce the amount of time required to perform the backup. Which of the following will best help you achieve this A. Back up to a RAID 0 instead. B. Add another tape drive and mirror the backup to the new drive. C. Back up to a mirrored volume instead. D. Back up to a RAID 5 instead.

2. You are currently performing weekly full backups of the Product database to tape and you need to find a way to ensure redundancy of the backup data. What should you do A. Perform the backup on one additional day per week. B. Back up the data twice to tape. C. Use a Database Snapshot to store an additional read-only copy of the data base. D. Use an additional tape drive to create a mirrored media set for the backup. 3. Which of the following is true regarding backup devices A. Any disk specified as a backup device must be local. B. You must provide a logical name for the backup device. C. Any tape device specified as a backup device must be local. D. A backup media set can consist of tapes, disks, or both.