Local hard disk: The virtual machine directly uses the disk of the physical machine. IO reading and writing occur on the physical ISCI hard disk. The IO performance is very excellent and the physical disk RAID5 redundancy protection. Cloud disk: Back-end network storage cluster, IO reading and writing are transmitted to the back-end distributed storage device blocks through the network, so the IO performance is limited by the network card performance, which is around 40MB/s, and may be lower in actual use; However, the advantage is that data security is extremely high, there is almost no data loss due to disk failure, good scalability, data can support hot migration, etc., and in the future, functions such as dynamic expansion will be based on cloud disks.
To sum up: If the business does not have very strict requirements for disk IO, it is recommended to buy a cloud disk; if the business has special requirements for IO, then it is better to buy a local disk.
The hard disk of the cloud host = cloud disk In fact, there was no such term as cloud disk before. Since some cloud servers started to use SSD as the hard disk, ordinary hard disks were called cloud disks
There are three major forms of network storage, namely block storage, file storage and object storage (I won’t copy the definitions, just search them online). The representative of block storage is SAN. To put it bluntly, it means replacing the hard disk cable with a network cable. After virtualization, "cloud disk" and "cloud hard disk" are actually in the form of block storage, which is equivalent to choosing different virtual hard disks to mount on the cloud host. The other two types, the representative of file storage is NAS, which is equivalent to separating the storage function and using an independent system to host it, so it can provide independent network file services. In the cloud system, I know that Alibaba Cloud can provide NAS, but I am not sure about the others; object storage abandons the traditional file system, separates files into objects, and uses independent APIs for access. This is provided by larger cloud service providers. .
I'm going too far... So the "cloud hard disk" here is understood by the questioner as a hard disk that can be mounted freely.
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Server remote hard drive
Cloud hard disk is a kind of cloud disk, which is provided to cloud hosts and is easy to expand
Can be understood as a hard drive, just in the sky. It’s called Yunpan
Local hard disk: The virtual machine directly uses the disk of the physical machine. IO reading and writing occur on the physical ISCI hard disk. The IO performance is very excellent and the physical disk RAID5 redundancy protection.
Cloud disk: Back-end network storage cluster, IO reading and writing are transmitted to the back-end distributed storage device blocks through the network, so the IO performance is limited by the network card performance, which is around 40MB/s, and may be lower in actual use; However, the advantage is that data security is extremely high, there is almost no data loss due to disk failure, good scalability, data can support hot migration, etc., and in the future, functions such as dynamic expansion will be based on cloud disks.
To sum up: If the business does not have very strict requirements for disk IO, it is recommended to buy a cloud disk; if the business has special requirements for IO, then it is better to buy a local disk.
The hard disk of the cloud host = cloud disk
In fact, there was no such term as cloud disk before. Since some cloud servers started to use SSD as the hard disk, ordinary hard disks were called cloud disks
The cloud hard disk here should refer to storing the hard disk data of the cloud server on another server.
There are three major forms of network storage, namely block storage, file storage and object storage (I won’t copy the definitions, just search them online). The representative of block storage is SAN. To put it bluntly, it means replacing the hard disk cable with a network cable. After virtualization, "cloud disk" and "cloud hard disk" are actually in the form of block storage, which is equivalent to choosing different virtual hard disks to mount on the cloud host.
The other two types, the representative of file storage is NAS, which is equivalent to separating the storage function and using an independent system to host it, so it can provide independent network file services. In the cloud system, I know that Alibaba Cloud can provide NAS, but I am not sure about the others; object storage abandons the traditional file system, separates files into objects, and uses independent APIs for access. This is provided by larger cloud service providers. .
I'm going too far... So the "cloud hard disk" here is understood by the questioner as a hard disk that can be mounted freely.