NFS
Installation
(root@server)_$: apt-get install nfs-common nfs-kernel-server
(user@client)_$: apt-get install nfs-common rpcbind
Upon starting the server, it will complain about not finding the /run/rpcbind/rpcbind.xdr and /run/rpcbind/portmap.xdr files. It is a bug in Ubuntu that does not affect to the server’s performance.
Server configuration
We will assume the server IP address is 192.168.1.191 for the rest of the examples.
(root@server)_$: mkdir -p /srv/share
(root@server)_$: chmod 0777 /srv/share
/etc/hosts.allow:
-----------------
...
portmap: 192.168.1.*
(root@server)_$: service portmap restart
/etc/exports:
-------------
...
# /srv/share
/srv 192.168.0.0/16(rw,root_squash,subtree_check)
/srv/share 192.168.0.0/16(rw,root_squash,subtree_check)
Check the /etc/idmapd.conf file. If everything is ok you will not have to change anything, but check it just in case.
/etc/idmapd.conf:
-----------------
[General]
Verbosity = 0
Pipefs-Directory = /run/rpc_pipefs
# set your own domain here, if id differs from FQDN minus hostname
# Domain = localdomain
[Mapping]
Nobody-User = nobody
Nobody-Group = nogroup
(root@server)_$: service nfs-kernel-server restart
Client configuration
Check the /etc/idmapd.conf file in the client too.
/etc/idmapd.conf:
-----------------
[General]
Verbosity = 0
Pipefs-Directory = /run/rpc_pipefs
# set your own domain here, if id differs from FQDN minus hostname
# Domain = localdomain
[Mapping]
Nobody-User = nobody
Nobody-Group = nogroup
Ubuntu 14 - Bug 1270445
To solve this bug you need to change the following:
/etc/default/nfs-common:
------------------------
...
NEED_GSSD="yes"
_$: service rpcbind restart
_$: rpc.gssd
If that does not work, reboot the server.
Test
Check the NFS server is running
(root@server)_$: rpcinfo -p | grep nfs
100003 2 tcp 2049 nfs
100003 3 tcp 2049 nfs
100003 4 tcp 2049 nfs
100003 2 udp 2049 nfs
100003 3 udp 2049 nfs
100003 4 udp 2049 nfs
Mount the directory and create a file on the client
(user@client)_$: sudo mkdir -p /tmp/share
(user@client)_$: sudo mount -t nfs -o rw,nosuid 192.168.1.191:/srv/share /tmp/share
(user@client)_$: cd /tmp/share/
(user@client)_$: touch a
(user@client)_$: echo "asd" > a
See if the changes went to the server
(root@server)_$: ll /srv/share/
total 4
-rw-r--r-- 1 wintenfox wintenfox 4 Dec 28 09:43 a
(root@server)_$: more a
asd
And unmount the directory in the client
(user@client)_$: cd /tmp/
(user@client)_$: sudo umount shared
Create a script to mount the directory
All of these changes are done in the client host.
/etc/init.d/mount-nfs-files:
----------------------------
#! /bin/sh
#
# skeleton example file to build /etc/init.d/ scripts.
# This file should be used to construct scripts for /etc/init.d.
#
# Written by Miquel van Smoorenburg <miquels@cistron.nl>.
# Modified for Debian
# by Ian Murdock <imurdock@gnu.ai.mit.edu>.
# Further changes by Javier Fernandez-Sanguino <jfs@debian.org>
#
# Version: @(#)skeleton 1.9 26-Feb-2001 miquels@cistron.nl
#
### BEGIN INIT INFO
# Provides: files shared directory
# Required-Start: $network
# Required-Stop: $network
# Default-Start: 2 3 4 5
# Default-Stop: 0 1 6
# Short-Description: Mount/umount files shared folder.
# Description: Mount/umount files shared folder.
### END INIT INFO
NAME="mount-nfs-files"
REMOTE="192.168.1.191"
REMOTE_DIR="/srv/share/files"
LOCAL_DIR="/home/<user>/shared/files"
case "$1" in
start)
mount -t nfs -o rw,nosuid ${REMOTE}:${REMOTE_DIR} ${LOCAL_DIR}
;;
stop)
umount ${LOCAL_DIR}
;;
restart)
umount ${LOCAL_DIR}
mount -t nfs -o rw,nosuid ${REMOTE}:${REMOTE_DIR} ${LOCAL_DIR}
;;
*)
echo "Usage: $NAME {start|stop|restart}"
exit 1
;;
esac
exit 0
Create the init scripts:
_$: chown root:root /etc/init.d/mount-nfs-files
_$: chmod 0755 /etc/init.d/mount-nfs-files
_$: update-rc.d mount-nfs-files defaults 99 00
_$: service mount-nfs-files start
If you ever decide to delete the script:
_$: update-rc.d -f mount-nfs-files remove
_$: rm /etc/init.d/mount-nfs-files
Troubleshooting
1) The command sudo mount -t nfs ... does not finish immediately in the client.
Check your iptables configuration and add the 2049 TCP and UDP port.
...
-A INPUT -p udp -m state --state NEW -m udp --dport 2049 -j ACCEPT
-A INPUT -p tcp -m state --state NEW -m tcp --dport 2049 -j ACCEPT
...
2) all_squash does not work.
- http://www.spinics.net/lists/linux-nfs/msg16592.html
- http://blog.seljebu.no/2012/05/nfs4-and-all_squash/
If the directory we want to share is inside the sharing directory, we need to bind it.
Example:
We want to share /srv/share/test
The sharing directory is /srv/share
(root@server)_$: mv /srv/share/test /srv/share/.test
(root@server)_$: mkdir /srv/share/test
(root@server)_$: mount --bind .test/ test
/etc/exports:
-------------
/srv 192.168.0.0/16(rw,no_root_squash,subtree_check)
/srv/share 192.168.0.0/16(rw,no_root_squash,subtree_check)
/srv/share/test 192.168.0.0/16(rw,all_squash,anonuid=65534,anongid=65534,subtree_check)
You can add this to fstab so that it is not affected by reboots:
/etc/fstab:
-----------
...
/srv/share/.test /srv/share/test none rw,bind 0 0
3) We can not unmount the directory because the NFS server is irresponsive (shutdown, no network connection, etc.).
(user@client)_$: umount -f /tmp/share
4) Directory appears as busy when unmounting.
(user@client)_$: umount -f -l /tmp/share
5) The changes that we made in .test are not reflected in test.
This can happen if we move the directory to somewhere else or we restore a backup overwriting the old directory. Creating and deleting files in those directories should not need these commands to see changes reflected.
(root@server)_$: mount --bind .test/ test/
(root@server)_$: mount -o remount,ro,bind .test/ test/
Configuration example
/etc/exports:
-------------
# /etc/exports: the access control list for filesystems which may be exported
# to NFS clients. See exports(5).
#
# Example for NFSv2 and NFSv3:
# /srv/homes hostname1(rw,sync,no_subtree_check) hostname2(ro,sync,no_subtree_check)
#
# Example for NFSv4:
# /srv/nfs4 gss/krb5i(rw,sync,fsid=0,crossmnt,no_subtree_check)
# /srv/nfs4/homes gss/krb5i(rw,sync,no_subtree_check)
#
/srv 192.168.0.0/16(rw,no_root_squash,subtree_check)
/srv/share 192.168.0.0/16(rw,no_root_squash,subtree_check)
/srv/share/files 192.168.0.0/16(rw,all_squash,subtree_check)
/etc/fstab:
-----------
# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point> <type> <options> <dump> <pass>
...
/srv/share/.files /srv/share/files none rw,bind 0 0