What is network file system in linux

What is NFS Linux?

NFS allows a system to share directories and files with others over a network. By using NFS, users and programs can access files on remote systems almost as if they were local files.

What is NFS used for?

The Network File System (NFS) is a mechanism for storing files on a network. It is a distributed file system that allows users to access files and directories located on remote computers and treat those files and directories as if they were local.

What is NFS used for Linux?

NFS is one of the easiest and most transparent ways to handle shared storage within an organization. Learn how to configure it on Red Hat Enterprise Linux. The Network File System (NFS) is a protocol that allows you to set up storage locations on your network.

What is the difference between FTP and NFS?

But NFS is a protocol that allows computer users to access files on a network, making it a distributed file system. Well FTP is used to communicate and transfer files between computers using the Transmission Control Protocol also known as the Internet.

What is advantage of NFS in Linux?

The NFS service has the following benefits: Enables multiple computers to use the same files, so everyone on the network can access the same data. Reduces storage costs by having computers share applications instead of needing local disk space for each user application.

NFS (Network File Systems) on Linux — 1

What is the major disadvantage of NFS?

• Based on RPC, which is inherently insecure. RPC communication should only be allowed behind a firewall, on a trusted network.
• NFSv4 and NFSv4. 1 may have limits in maximal bandwidth, so NFS can slow down in the event of high traffic loads. This has improved in version 4.2.

What is the downside of NFS?

Some of the drawbacks of using NFS include the following: Dependence on RPCs makes NFS inherently insecure and should only be used on a trusted network behind a firewall. Otherwise, NFS will be vulnerable to internet threats.

What are the pros and cons of NFS?

In this tutorial, we discussed the Network File System in detail. The main benefits of using NFS are centralized data storage, increased efficiency, data security, and scalability. However, it’s not a good choice for sharing sensitive data over public networks and doesn’t support hierarchical storage management.

Should I use NFS?

NFS is the better choice for transferring small and medium files over the network (for example, files of about 1 MB and less in size). Performance for both protocols is similar when transferring large files (for example, 500 MB files). NFS is faster than SMB when using encryption.

Is NFS a file transfer protocol?

NFS, or Network File System, was designed in 1984 by Sun Microsystems. This distributed file system protocol allows a user on a client computer to access files over a network in the same way they would access a local storage file. Because it is an open standard, anyone can implement the protocol.

What is the difference between FTP and NFS in Linux?

Ftp stands for File Transfer Protocol which is used for transferring files from one location to another location, normally using Internet. With FTP you can send very big files. NFS stands for Network File system which allows a user to access a file usually in a server.

How fast is NFS Linux?

The NFS server and client communicate over a 100 MB per second Ethernet network. When sequentially writing a small file, the throughput averages around 10 MB per second. However, when writing a very large file, the throughput average drops to well under 1 MB per second.

How to setup NFS in Linux?

1. Setup NFS. NFS mount needed at least two machines. .
2. IP address Details of Server & Client.
3. Configuring NFS Server. .
4. Exporting the Share Directory. .
5. Explanation. .
6. Configure Client. .
7. Creating Mount Point for Share Directory. .
8. Mounting the Share Directory.

Is NFS outdated?

It is also known as RFC-1094 and works on the User Datagram Protocol(UDP) which is a stateless network connection. It has a storage of 32-bit with a max storage size of 4.2 GB and the data transfer rate is 8kb and needs to commit after the transfer is done. NFS version 2 is now outdated and of no use as of now.

Do people still use NFS?

Today there are only two versions of the NFS protocol left in use: Version 3, published in 1995, and version 4 in 2000. NFS 3 is still by far the most common version of the protocol and is the only one supported by Windows clients.

Is NFS a block or file?

The storage system of Network Attached Storage and hard drives is a file level storage. Here in this storage system, the NFS (Network file system) or Server Block Message (SBM) or Common Internet file system (CIFS) protocol is used for storage and the files are accessed from the bulk.

Is NFS a security risk?

NFS like any other unprotected network protocol is vulnerable to two types of attacks: eavesdropping and impostor attack.

What is difference between SMB and NFS?

NFS has no fast file find; SMB has fast find. NFS no server and printer browsing, while SMB has server and printer browsing. NFS slower reads and writes; SMB faster. NFS better with small files, while SMB fine with small files but better with large files.

What ports are needed for NFS?

NFS uses port 2049. NFSv3 and NFSv2 use the portmapper service on TCP or UDP port 111. The portmapper service is consulted to get the port numbers for services used with NFSv3 or NFSv2 protocols such as mountd, statd, and nlm.

Which protocol is better than NFS?

The main difference between these two types of communication systems are CIFS can used only in Windows operating system, whereas NFS can be used in UNIX and LINUX based systems. In terms of security, CIFS provides better network security than NFS.

Is NFS safer than SMB?

In random read, NFS and SMB fare equally with plain text. However, NFS is better with encryption. In the case of random writing, NFS is better than SMB in both plain text and encryption. If you use rsync for file transfer, NFS is a better choice in plain text and encryption.

Does NFS work over Internet?

NFSv4 is the most recent version of the NFS protocol you can use. It can work on the internet and through firewalls. It does not require an rpcbind service, making it easier to run in more places. The Transmission Control Protocol or TCP works in this NFS format.

Why is NFS so slow?

If access to remote files seems unusually slow, ensure that access time is not being inhibited by a runaway daemon, a bad tty line, or a similar problem. Use the nfsstat command to gather information about your network connections. To set MTU size, use the SMIT fast path, smit chif .

What are the limits of NFS file system?

The NFS protocol supports a maximum of 16 group IDs (GIDs) per user and any additional GIDs are truncated from NFS client requests. For more information, see Access denied to allowed files on NFS file system..

What is the difference between NFS and CIFS?

NFS and CIFS are protocols allowing client systems to view and access files stored on a remote device, such as a server or a PC. The main difference between NFS and CIFS is that NFS allows sharing remote files between servers, while CIFS allows accessing the files over the network.

Источник

dimaskiddo / nfs-intro.md

Network File System or NFS is basically developed for sharing of files and folders between Linux/Unix systems by Sun Microsystems in 1980. NFS, like many other protocols, builds on the Open Network Computing Remote Procedure Call (ONC RPC) system.

The NFS is an open standard defined in a Request for Comments (RFC), allowing anyone to implement the protocol. It allows you to mount your local file systems over a network and remote hosts to interact with them as they are mounted locally on the same system. With the help of NFS, we can set up file sharing between Unix to Linux system and Linux to Unix system.

Currently, there are three versions of NFS. NFS version 2 (NFSv2) is older and widely supported. NFS version 3 (NFSv3) supports safe asynchronous writes and is more robust at error handling than NFSv2, it also supports 64-bit file sizes and offsets, allowing clients to access more than 2Gb of file data.

NFS version 4 (NFSv4) works through firewalls and on the Internet, no longer requires an rpcbind service, supports ACLs, and utilizes stateful operations.

All versions of NFS can use Transmission Control Protocol (TCP) running over an IP network, with NFSv4 requiring it. NFSv2 and NFSv3 can use the User Datagram Protocol (UDP) running over an IP network to provide a stateless network connection between the client and server

When using NFSv2 or NFSv3 with UDP, the stateless UDP connection (under normal conditions) has less protocol overhead than TCP. This can translate into better performance on very clean, non-congested networks. However, because UDP is stateless, if the server goes down unexpectedly, UDP clients continue to saturate the network with requests for the server.

In addition, when a frame is lost with UDP, the entire RPC request must be retransmitted. With TCP, only the lost frame needs to be resent. For these reasons, TCP is the preferred protocol when connecting to an NFS server

The mounting and locking protocols have been incorporated into the NFSv4 protocol. The server also listens on the well-known TCP port 2049. As such, NFSv4 does not need to interact with rpcbind , lockd , and rpc.statd daemons. The rpc.mountd daemon is required on the NFS server to set up the exports

After TCP wrappers grant access to the client, the NFS server refers to the /etc/exports configuration file to determine whether the client is allowed to access any exported file systems. Once verified, all file and directory operations are available to the user

• NFS allows local access to remote files
• It uses standard client/server architecture for file sharing between all *nix based machines
• With NFS it is not necessary that both machines run on the same Operating System (OS)
• With the help of NFS we can configure centralized storage solutions
• Users get their data irrespective of physical location
• No manual refresh needed for new files
• Newer version of NFS also supports acl and pseudo root mounts
• Can be secured with Firewalls and Kerberos

NFS on Linux launch as System-V service with some core loaded as kernel extensions. The NFS server package includes three facilities, included in the portmap and nfs-utils packages

• portmap : It maps calls made from other machines to the correct RPC service (not required with NFSv4)
• nfs : It translates remote file sharing requests into requests on the local file system
• rpc.mountd : This service is responsible for mounting and unmounting of file systems

There are several files related to NFS configuration on Linux that we must know

• /etc/exports : Its a main configuration file of NFS, all exported files and directories are defined in this file at the NFS Server end
• /etc/fstab : To mount a NFS directory on your system across the reboots, we need to make an entry in /etc/fstab
• /etc/sysconfig/nfs : Configuration file of NFS to control on which port rpc and other services are listening

Источник