You might be wondering what distributed file systems provide and how this relates to WebDAV distributed filesystems comparison metrics. They are the ones responsible for accessing of data kept in the servers with the use of online file warehouses. Through a file system interface, a file can be opened, checked, or closed. It can also be read, rewritten and locked.  It can also perform listing, creating and deleting the directory.

WebDAV Distributed FileSystems Comparison

Why are distributed file systems even useful?

Simple, the answer is for a number of ways. This includes the sharing of data across multiple users, user mobility, and transparency of location as well as backing up of files and centralizing management.

Through this, data are organized in a way that they belong in a specific directory.

For distributed file systems, they can be classified into three components, namely client-side, server-side, and communication layer.

CLIENT SIDE

For client-side, it is a question of what needs to happen in order to allow applications to access a file in a similar way that the local file is accessed.

One example of this is the basic UNIX. Files are accessed the same way as they are accessed in the local file support.

VFS interception also happens in the client-side component. There is a standard interaction between files, and it is usually handled by the kernel process. Files are stored in a local cache, and they are retransmitted whenever necessary.

In VFS interception, a pluggable file systems are being provided. Through the user, the reading process is called, and kernel sends off the instruction through some interception. It could either be to check the local cache or put the process to sleep.

SERVER SIDE

For server-side, it is usually focused on how to request from clients is paid attention to.

Two server-side examples are mountd and nfsd. The formers cater initial file handling for the directory that was exported. The process goes through the client exposing nfs_mount to mountd. Then, mountd will perform the gist of its action which is to check if the pathname sent is a directory and if that directory must be sent out to the client.

Meanwhile, for the latter which is nfsd, RPC calls are being answered to get a response from the local file system. The reply is sent through RPC. Both the two examples of server-side use the RPC as their underlying working principle to perform actions.

WebDAV Distributed Filesystems Comparison : The Communication Layer

For the communication layer, it is a question of whether the IP or protocol is on some level of abstraction.

One example of the communication layer is the Remote Procedure Calls or RPC. There are two processes involved namely Remote Procedure Calls Call and Remote Procedure Calls Reply. Failure in handling these processes can either lead to a time-out or a re-issue.

Involved in this type is the Extended Data Representation or XDR where in integers are recorded in a specific format called endian. Marshaling, as well as unmarshalling of data, can also happen in Extended Data Representation. It can perform through three subdivisions namely strings, arrays and opaque.

 

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