A LUN (Logical Unit Number) is created by a storage administrator using a storage management tool provided by the storage vendor. The process involves several steps, depending on the specific storage system and its configuration.
Steps to Create a LUN:
- Identify the storage pool: Select the storage pool where the LUN will be created. This pool is a collection of physical storage resources, like disks or SSDs, that are grouped together for efficient management.
- Define the LUN size: Specify the size of the LUN in gigabytes (GB) or terabytes (TB). The size should be sufficient to accommodate the data that will be stored on the LUN.
- Assign a LUN ID: Give the LUN a unique identifier, which is a number that differentiates it from other LUNs on the storage system.
- Select the LUN type: Choose the type of LUN based on the intended use case. Common types include:
- Block LUN: Provides raw block storage, allowing the host to directly access and manage data blocks.
- File LUN: Provides access to files and directories through a file system.
- Configure access permissions: Determine which servers or hosts will have access to the LUN and what level of access they will have (read-only, read-write, etc.).
- Format the LUN: Depending on the LUN type, the storage system might need to format the LUN to make it usable. This process creates a file system on the LUN, allowing data to be stored and retrieved.
Example:
Let's say you need to create a 100 GB LUN for a virtual machine. You would use the storage management tool to:
- Select the appropriate storage pool.
- Specify the LUN size as 100 GB.
- Assign a unique LUN ID.
- Choose the block LUN type.
- Grant access to the virtual machine.
Once these steps are completed, the LUN is created and ready to be used.
Practical Insights:
- LUNs are commonly used in virtualized environments to provide storage for virtual machines.
- They can also be used for database servers, application servers, and other applications that require dedicated storage.
- The size of a LUN should be carefully considered to ensure it meets the needs of the application or workload.
