Design storage architecture based on capacity and I/O requirements
The storage architecture and disk types that you select for your environment can affect system performance.
In this section:
- Choose a storage architecture
- Choose disk types
- Choose RAID types
Choose a storage architecture
Direct Attached Storage (DAS),
Storage Area Network (SAN),
and Network Attached Storage (NAS) storage architectures are supported with SharePoint Server 2010, although NAS is only supported for use with content databases that are configured to use remote BLOB storage. Your choice depends on factors within your business solution and your existing infrastructure.
Any storage architecture must support your availability needs and perform adequately in IOPS and latency. To be supported, the system must consistently return the first byte of data within 20 milliseconds (ms).
Direct Attached Storage (DAS)
DAS is a digital storage system that is directly attached to a server or workstation, without a storage network in between. DAS physical disk types include Serial Attached SCSI (SAS) and Serial Attached ATA (SATA).
In general, Microsoft recommend that you choose a DAS architecture when a shared storage platform cannot guarantee a response time of 20 ms and sufficient capacity for average and peak IOPs.
Storage Area Network (SAN)
SAN is an architecture to attach remote computer storage devices (such as disk arrays and tape libraries) to servers in such a way that the devices appear as locally attached to the operating system (for example, block storage).
In general, we recommend that you choose a SAN when the benefits of shared storage are important to your organization.
The benefits of shared storage include the following:
- Easier to reallocate disk storage between servers.
- Can serve multiple servers.
- No limitations on the number of disks that can be accessed.
Network Attached Storage (NAS)
A NAS unit is a self-contained computer that is connected to a network. Its sole purpose is to supply file-based data storage services to other devices on the network. The operating system and other software on the NAS unit provide the functionality of data storage, file systems, and access to files, and the management of these functionalities (for example, file storage).
NAS is only supported for use with content databases that are configured to use remote BLOB storage. Any network storage architecture must respond to a ping within 1 ms and must return the first byte of data within 20 ms. This restriction does not apply to the local SQL Server FILESTREAM provider, because it only stores data locally on the same server.
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