Questions tagged [nfs]

Network File System (NFS) is a network file system protocol originally developed by Sun Micro systems in 1984, allowing a user on a client computer to access files over a network in a manner similar to how local storage is accessed. NFS, like many other protocols, builds on the Open Network Computing Remote Procedure Call (ONC RPC) system. The Network File System is an open standard defined in RFCs.

Original NFS version

The implementation details are defined in RFC 1094. Sun used version 1 only for in-house experimental purposes. When the development team added substantial changes to NFS version 1 and released it outside of Sun, they decided to release the new version as v2, so that version interoperation and RPC version fall back could be tested.

NFSv2

Version 2 of the protocol (defined in RFC 1094, March 1989) originally operated entirely over UDP. Its designers meant to keep the protocol stateless, with locking (for example) implemented outside of the core protocol. NFSv2 only allowed the first 2 GB of a file to be read.

NFSv3

Version 3 (RFC 1813, June 1995) added:

  • support for 64-bit file sizes and offsets, to handle files larger than 2 gigabytes (GB)
  • support for asynchronous writes on the server, to improve write performance
  • additional file attributes in many replies, to avoid the need to re-fetch them
  • a READDIRPLUS operation, to get file handles and attributes along with file names when scanning a directory
  • assorted other improvements.

At the time of introduction of Version 3, vendor support for TCP as a transport-layer protocol began increasing. While several vendors had already added support for NFS Version 2 with TCP as a transport, Sun Micro systems added support for TCP as a transport for NFS at the same time it added support for Version 3. Using TCP as a transport made using NFS over a WAN more feasible.

NFSv4

Version 4 (RFC 3010, December 2000; revised in RFC 3530, April 2003), influenced by AFS and CIFS, includes performance improvements, mandates strong security, and introduces a stateful protocol. Version 4 became the first version developed with the Internet Engineering Task Force (IETF) after Sun Micro systems handed over the development of the NFS protocols.

NFS version 4 minor version 1 (NFSv4.1) has been approved by the IETF and received an RFC number 5661 since Jan 2010. The NFSv4.1 specification aims:

  • To provide protocol support to take advantage of clustered server deployments including the ability to provide scalable parallel access to files distributed among multiple servers (pNFS extension).
  • to provide sessions and Exacely One Semantic (EOS)
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Which ports do I need to open in the firewall to use NFS?

I'm running Ubuntu 11.10 - setting up NFS to share a directory among many other servers. Which ports are required to be opened on the firewall?
kenny
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How to properly set permissions for NFS folder? Permission denied on mounting end.

I'm trying to connect to an NFS folder on my dev server. The owner of the folder on the dev server is darren and group darren. When I export and mount it to my Mac using the Disk Utility it mounts, but then when I try to open the folder is says I do…
Darren
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Mapping UID and GID of local user to the mounted NFS share

I have a server with NFSv4. I am mounting contents of the home folder of remote user to local host. Able to read and write contents, but when I am checking ownership of files at the mounted volume from the local host, they all belongs to…
Alexander
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.nfsXXXX files appearing, what are those?

I have an application running (on RHEL5) that streams data onto an NFS share. Recently, I saw a lot of .nfsXXXX... (xxx being a hexadecimal number) appearing in its working directory, where the application writes hourly files and later moves them to…
nos
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Why rsync is faster than NFS?

Few days ago I noticed something rather odd (at least for me). I ran rsync copying the same data and deleting it afterwards to NFS mount, called /nfs_mount/TEST. This /nfs_mount/TEST is hosted/exported from nfs_server-eth1. The MTU on both network…
grs
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Troubleshooting latency spikes on ESXi NFS datastores

I'm experiencing fsync latencies of around five seconds on NFS datastores in ESXi, triggered by certain VMs. I suspect this might be caused by VMs using NCQ/TCQ, as this does not happen with virtual IDE drives. This can be reproduced using…
exo_cw
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chown on a mounted NFS partition gives "Operation not permitted"

I have a remote partition that i have mounted locally using NFS. 'mount' gives 192.168.3.1:/mnt/storage-pools/ on /pools type nfs (rw,addr=192.168.3.1) On the server i have in exports: /mnt/storage-pools …
Disco
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unable to write to mount point (nfs-server), getting "Permission denied"

I'm trying to configure NFS between two RHEL7 nodes: first node: [root@ip-10-164-175-246 ~]# cat /etc/redhat-release Red Hat Enterprise Linux Server release 7.0 (Maipo) [root@ip-10-164-175-246 ~]# rpm -q…
alexus
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Are there any free NFS clients for Windows 7?

I have Windows 7 Professional, but the NFS Client for Windows is only included in the Enterprise and Ultimate editions. I would like to connect some Windows machines to our NFS server so I can drop the Samba Server we are currently using. Are there…
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Unmount a nfs mount where the nfs server has disappeared

Server A used to be a NFS server. Server B was mounting an export of that. Everything was fine. Then A died. Just switched off. Gone. Vanished. However that folder is still mounted on B. I obviously can't cd into it or anything. However umount…
Amandasaurus
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What are the advantages/disadvantages of hard versus soft mounts in UNIX?

This question may vary between distros but, in general, what are the advantages/disadvantages of using a hard or soft mount in the UNIX world? Are there certain situations where one is more beneficial or are the uses fairly universal?
Aaron K
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Is it feasible to have home folder hosted with NFS?

I'm planning to deploy some kiosk computers and would like to leave them with a small pendrive as boot disk, keeping the rest at an easy to back up server, ala LTSP. Right now I'm pondering two options. An NFSed /home/, or a local copy of ~/ copied…
voyager
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NAS Performance: NFS vs Samba vs GlusterFS

I am planning my new shared storage infrastructure for a small webserver farm. Therefore i ran a lot of tests with a lot of NAS filesystems. By doing so, i got some unexpected results and would like to know whether somebody here can confirm this. In…
Linus Ardberk
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Understanding NFS4 (Linux server)

I've been a bit bothered by NFS4 on Linux. Some information 'out there' seems to conflict with other information, and other information appears hard to find. So here are a couple of things that caught my attention, hopefully someone out there can…
drumfire
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Why is an nfs server mounted as rw returning read only filesystem errors

I am working on a Ubuntu Server 64bit. I have mounted an nfs as rw, but whenever I try to edit anything on the mountpoint in question, I get a read-only filesystem error my etc/fstab reads: #
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