Introduction To Mount Point In SQL Server

All storage devices, from disk partitions to a floppy or CD drive, always require mounting before being used. However, a mount point is a mounted volume within another folder or volume. It is also possible in Windows to perform similar actions with multiple Windows disks. As everybody knows, there are initially 26 drive letters are available for assignment. After subtracting the reserved set of drives, i.e. A, B and, C, a user is left with 23 letters. Due to that, there is not much space available if a user is planning to use many data locations per instance. However, a multiple SQL Server instances require multiple disk sets to transfer input/ output operation. A user may plan to use these four drive letters for a single instance and plan to use separate assignment for

• SQL Server Logs

• SQL Server tempdb

• SQL Server data

• SAL Server backups

Here, SQL Server mount points will allow users to use single drive letter for each selected location. Moreover, for each of the separate physical location, it implements the separate physical drive.

More About SQL Server Mount Points

Mount Point is a file system location under which a physical disk partition is mounted or referenced in order to have complete utilization of disk space. In this, a user begins with the reference root that is commonly known as disk root. Always make sure that root disk is as small as possible to avoid creating data on root disk by multiple users. All this makes administration easier. Apart from all this, also make sure that all input/ output bound for the Mount Point occurs only on mounted physical disk rather on the root disk. For example,

Root disk 1 M - (Windows disk 2)

Now, create the multiple mount points in the following configuration for a single instance like,

• M:\SQLBak (Windows disk 3)

• M:\SQLTmp (Windows disk 4)

• M:\SQLLog (Windows disk 5)

• M:\SQLData (Windows disk 6)

Always keep in mind that mount points are a separate physical drive from Windows disk management. If a user wants to create multiple root disks and multiple instances of SQL Server, then it will create it in the way  given below,

• Root disk 1 E: (Windows disk 2)

• Root disk 2 H: (Windows disk 3)

• Root disk 3 I: (Windows disk 4)

• Root disk 4 M: (Windows disk 5)

A user will have multiple mount points and each instance will have four different unique physical disks mounted under like,

• Instance1 E:\INST1, H:\INST1, I:\INST1, M:\INST1 (Windows disks 6-9)

• Instance 2 E INST2, H:\INST2, I:\INST2, M:\INST2 (Windows disks 10-3)

• Instance 3 E:\INST3, H:\INST3, I:\INST3, M:\INST3 (Windows disks 14-7)

It is pretty clear from the above example that management becomes more complex whenever multiple root disks and mounted volumes are created.

Points to Remember About SQL Server Mount Points

There are some points that a user should always keep in mind and all of them are listed below,

• There should be no propagation of the permission between the root drive file system and mount point file system, both of them controlled separately.

• There should be no data created on root drive, it is a root tree for the new volumes.

• Always create or install the software into a folder under the mount point in order to have the correct propagation of permission.

• Mount points are compatible with all SQL Server 2000 configuration.

How to Setup a New Partitions?

Before formatting disks within disk management, a user first needs to decide the disk type and partition type, which is to be used. In general, there are two disk types that are possible i.e. Basic and Dynamic. Generally, basic type is commonly used for the cluster support.

• Basic Disk Type
  It is a default disk type used by Windows OS.
  
  
• Dynamic Disk Type
  Only useful while creating spanned volumes or software RAID systems. However, it is rarely used by the Windows OS.

Apart from disk type, there iaretwo different partition types i.e. MBR and GPT that can easily be used.

• MBR
  Master Boot Record partition type allows maximum four partitions per disk i.e. 3 primary and 1 extended.
  
  
• GPT
  GUID partition type allows very large disk space. It allows maximum of 128 partitions. Moreover, it is more resistant to corruption and efficient in use.

Benefits of Using Mount Points in SQL Server

Mount Point in SQL Server is having various advantages and all of them are listed below:

• Increase Hardware Utilization
  Active- Active clustering works in configuration rather than keeping the second node in the cluster to remain idle. However, a SQL instance can be run on both the nodes simultaneously. This will help to increase the hardware utilization with mount points.

• Flexibility
  Mount points also increase the flexibility because mounted volumes increased options available for use.

• Cost Saving
  Cost is mainly based on the SQL Server licensing. Therefore, the cost remains same always for one instance or 7 instances of it.

• Overcome Drive Letter Limitation
  A user can install any number of instances on a single cluster. However, it overcomes the limitation faced by the users related to a number of a drive letter.

• Reduced Administrative Overhead
  SQL Server mount points also helps in reducing the administrative overhead. With the help of single root mount volume dedicated to each SQL instance, it manages multiple volumes between cluster nodes.

Conclusion

Mount Points in SQL Server are used for physical disk partition to have a complete utilization of space available on disk. Therefore, mounting in SQL Server is very important. However, in this post, we have covered all possible information regarding SQL Server mount point that will help users in having a better understanding of the using mounting. Moreover, there are various advantages of using mount point in SQL Server that were also discussed.