Nas nfs in Network Storage

We know that NFS is a network file system and plays an important role in network protocols. With the development of network storage. It has made great progress in this area. Here we will introduce the application of nas nfs in VMware. NAS is a simple network storage. As we all know, it is easy to implement, operate and manage. This is similar to VMware ESX. Using NAS in ESX network storage is a good choice.

Network File System NFS is required to use NAS in ESX. Currently, CIFS is not supported ). Users often ask the following question: "Why is nfs nas not so frequently used in VMware ESX environments ?" Traditionally, FC or iSCSI SAN storage is more suitable for VMware ESX, but this view may not be completely correct.

Advantages of using nas nfs in VMware ESX

All ESX clients are saved as *. vmdk files. It is very important to realize this. In terms of architecture, NAS optimizes storage, management, and file provision. File Management is generally considered simpler than logical unit number LUN management. Therefore, in terms of logic, NAS is a simpler network storage than local network SAN.

If there are dozens of Virtual Machine VMS in the system), technically speaking, write the Virtual Machine File System (VMFS) to SAN storage, it is very helpful to integrate all vmdks into a single LUN. However, if the system has thousands of virtual machines, nas nfs is a more efficient network storage method.

For example, NAS allows you to group similar VMDK files into different folders. One folder can store all desktop images, one folder can store all Microsoft Exchange servers, and the other folder can store SQL servers, and so on. In addition, many NAS products also provide very useful and attractive file management capabilities. For example, deduplication, information lifecycle management (ILM), service-level QoS), zero impact snapshot, cloning, security, and verification, and mature local and remote replication synchronization and Asynchronization ).

Advanced NAS features such as deduplication, ILM, and QoS can have a huge positive impact on Storage types and the space occupied by VMDK. VMware users generate many server images, each of which occupies 1 GB to 10 Gb of storage space. The storage space is not large. However, the accumulation may be amazing.

NAS-based deduplication of file-level, block-level, variable block size and Application Awareness) can reduce these images by up to 97% or higher, which means the cost of real money is reduced. However, it is important that this technology can only be used when the performance service level of VM applications is not high. This technology is applicable to ISO files, templates, and desktop images. The de-duplicated VMDK stored on NFS can achieve a reasonable running speed, but the speed is lower than the average NAS or SANFC or iSCSI-based storage. The performance after deduplication is generally suitable for virtual machines with low usage.

NAS can continuously move application files to different service levels and storage layers. This inherent capability can effectively use low-cost storage and archiving devices. However, not all production and non-production VMS require the same performance level. Some NAS systems can determine the performance service priority of each VM according to the rules, detect the actual performance they have achieved, and then ensure that the service level can be implemented transparently.

In terms of disaster Recovery, many NAS systems can work with VMware vCenter Site Recovery Manager (SRM. The NAS system can copy the virtual machine data of the entire group as a unit, which greatly simplifies the replication.

Disadvantages of using nas nfs in VMware ESX

The biggest disadvantage of using nas nfs in VMware ESN is generally considered to be performance. To some extent, NAS performance is slightly slower than FC or iSCSI SAN storage. In fact, it is difficult for most virtual machines to see the difference, because storage is rarely a bottleneck in the system. At the same time, there are many fast-paced NAS systems on the market, making the difference more difficult to perceive, such as BlueArc, EMC, NetApp, OnStor, Reldata ).

Another way to further narrow the performance gap is to use multiple networks. This network structure balances loads and creates multiple paths for different NFS sharing points.

Another disadvantage is that nas nfs does not support the advanced features of VMware ESX. This is not true. There is only one special case. Nas nfs supports VMware VMotion, DRS, vCenter SRM, HA-DR, and even VMware centralized backup. Currently, the only thing that cannot be supported is the migration of data between different Storage systems without interrupting the Storage VMotion VM ).

The last disadvantage is that it is often asserted that Windows VM clients cannot use nas nfs effectively because they cannot start Microsoft from NFS and does not support Windows from NFS ). NFS can be used in Windows virtual machines, because VMware has built NFS into the disk Virtual Layer of ESX to overcome this disadvantage. Some IT experts are surprised. ESX processes the NFS protocol so that all operations and protocols are separated from the operating system.

Summary of nas nfs and VMware ESX

For VMware ESX virtual machines, nas nfs is an excellent network storage candidate because it is easy to use and provides outstanding value.

In addition, there can be a NAS and SAN hybrid network storage solution in the VMware environment, where the appropriate method is used. This is a more reasonable option, especially when some network storage method already exists in the infrastructure.