Thursday, January 15, 2009

Recommended and Best practices of RAID levels for SQL Server.

RAID-0
1. RAID-0 uses disk striping; that is, it writes data across multiple hard disk partitions in what is called A stripe set.
2. This can greatly improve speed because multiple hard disks are working at the same time.
3. You can implement RAID-0 through the use of Windows Server software or third-party hardware.
4. Although RAID-0 gives you the best speed, it does not provide any fault-tolerance.
5. If one of the hard disks in the stripe set is damaged, you lose all of your data.
6. Because of the lack of fault tolerance, Microsoft doesn’t recommend storing any of your SQL Server data on RAID-0 volumes. 

RAID-1 
1. RAID-1 uses disk mirroring. Disk mirroring actually writes your information to disk twice — once to the primary file and once to the mirror. This gives you excellent fault-tolerance, but it is fairly slow, because you must write to disk twice. 
2. This is the recommended place for storing your transaction logs because RAID-1 gives fast sequential write speed a requirement for transaction logs. 

RAID-5 
1. RAID-5 striping with parity — writes data to the hard disk in stripe sets.
2. Parity checksums will be written across all disks in the stripe set.
3. This gives you excellent fault-tolerance as well as excellent speed with a reasonable amount of overhead.
4. You can use the parity checksums to re-create information lost if a single disk in the stripe set fails.
5. If more than one disk in the stripe set fails, however, you will lose all your data.
6. Microsoft recommends storing your data files on this type of RAID because data files require fast read speed as opposed to transaction logs, which need fast write speed. 

RAID-10 
1. You should use RAID-10 (sometimes referred to as RAID 0+1) in mission-critical systems that require 24/7 uptime and the fastest possible access.
2. RAID-10 implements striping with parity as in RAID-5 and then mirrors the stripe sets.
3. So, you get the incredible speed and fault tolerance, but RAID-10 has a drawback.
4. Unless you can afford a RAID-10 array, Microsoft suggests a combination of RAID-5 and RAID-1.
5. In this scenario, you place your data files on the RAID-5 array for speed and redundancy. You place your transaction log files on the RAID-1 drives so they can be mirrored.



RAID Levels and SQL Server. Raid Configuration in sql server 2012. RAID 5 and SQL Server. RAID 10 and SQL Server. RAID 0 and SQL Server. RAID recomendations. RAID levels for system databses. RAID configuration for SQL Server 2008 Database . Disk Set up for SQL Server 2008 on SAN Storage. SAN and Raid Levels. SQL Server and Storage. Optimal RAID setup for SQL server. SQL Server DBA Quiz. What RAID level do you use on SharePoint databases. Help me choose a RAID level combination for a SQL Server 2012. RAID 10 vs. RAID 5 Performance. RAID for SQL Server: Advantages and Disadvantages. Comparing Different Implementations of RAID Levels. Recommended and Best practices RAID levels for SQL Server 2005.

0 comments:

Post a Comment