Setting Up An NFS Server And Client On Debian Etch
Version 1.0
Author: Falko Timme
This guide explains how to set up an NFS server and an NFS client on Debian Etch. NFS stands for Network File System; through NFS, a client can access (read, write) a remote share on an NFS server as if it was on the local hard disk.
I do not issue any guarantee that this will work for you!
1 Preliminary Note
I'm using two Debian systems here:
- NFS Server: server.example.com, IP address: 192.168.0.100
- NFS Client: client.example.com, IP address: 192.168.0.101
2 Installing NFS
server:
On the NFS server we run:
apt-get install nfs-kernel-server nfs-common portmap
client:
On the client we can install NFS as follows:
apt-get install nfs-common portmap
3 Exporting Directories On The Server
server:
I'd like to make the directories /home and /var/nfs accessible to the client; therefore we must "export" them on the server.
When a client accesses an NFS share, this normally happens as the user nobody. Usually the /home directory isn't owned by nobody (and I don't recommend to change its ownership to nobody!), and because we want to read and write on /home, we tell NFS that accesses should be made as root (if our /home share was read-only, this wouldn't be necessary). The /var/nfs directory doesn't exist, so we can create it and change its ownership to nobody and nogroup:
mkdir /var/nfs
chown nobody:nogroup /var/nfs
Now we must modify /etc/exports where we "export" our NFS shares. We specify /home and /var/nfs as NFS shares and tell NFS to make accesses to /home as root (to learn more about /etc/exports, its format and available options, take a look at
man 5 exports
)
vi /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) hostname2(ro,sync) # # Example for NFSv4: # /srv/nfs4 gss/krb5i(rw,sync,fsid=0,crossmnt) # /srv/nfs4/homes gss/krb5i(rw,sync) # /home 192.168.0.101(rw,sync,no_root_squash) /var/nfs 192.168.0.101(rw,sync) |
(The no_root_squash option makes that /home will be accessed as root.)
Whenever we modify /etc/exports, we must run
exportfs -a
afterwards to make the changes effective.
4 Mounting The NFS Shares On The Client
client:
First we create the directories where we want to mount the NFS shares, e.g.:
mkdir -p /mnt/nfs/home
mkdir -p /mnt/nfs/var/nfs
Afterwards, we can mount them as follows:
mount 192.168.0.100:/home /mnt/nfs/home
mount 192.168.0.100:/var/nfs /mnt/nfs/var/nfs
You should now see the two NFS shares in the outputs of
df -h
client:~# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 30G 748M 27G 3% /
tmpfs 63M 0 63M 0% /lib/init/rw
udev 10M 52K 10M 1% /dev
tmpfs 63M 0 63M 0% /dev/shm
192.168.0.100:/home 30G 764M 27G 3% /mnt/nfs/home
192.168.0.100:/var/nfs
30G 764M 27G 3% /mnt/nfs/var/nfs
client:~#
and
mount
client:~# mount
/dev/sda1 on / type ext3 (rw,errors=remount-ro)
tmpfs on /lib/init/rw type tmpfs (rw,nosuid,mode=0755)
proc on /proc type proc (rw,noexec,nosuid,nodev)
sysfs on /sys type sysfs (rw,noexec,nosuid,nodev)
udev on /dev type tmpfs (rw,mode=0755)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev)
devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=620)
192.168.0.100:/home on /mnt/nfs/home type nfs (rw,addr=192.168.0.100)
192.168.0.100:/var/nfs on /mnt/nfs/var/nfs type nfs (rw,addr=192.168.0.100)
client:~#
5 Testing
On the client, you can now try to create test files on the NFS shares:
client:
touch /mnt/nfs/home/test.txt
touch /mnt/nfs/var/nfs/test.txt
Now go to the server and check if you can see both test files:
server:
ls -l /home/
server:~# ls -l /home/
total 4
drwxr-xr-x 2 administrator administrator 4096 2007-04-23 14:25 administrator
-rw-r--r-- 1 root root 0 2007-11-29 21:43 test.txt
server:~#
ls -l /var/nfs
server:~# ls -l /var/nfs
total 0
-rw-r--r-- 1 nobody nogroup 0 2007-11-29 21:49 test.txt
server:~#
(Please note the different ownerships of the test files: the /home NFS share gets accessed as root, therefore /home/test.txt is owned by root; the /var/nfs share gets accessed as nobody, therefore /var/nfs/test.txt is owned by nobody.)
6 Mounting NFS Shares At Boot Time
Instead of mounting the NFS shares manually on the client, you could modify /etc/fstab so that the NFS shares get mounted automatically when the client boots.
client:
Open /etc/fstab and append the following lines:
vi /etc/fstab
[...] 192.168.0.100:/home /mnt/nfs/home nfs rw,sync,hard,intr 0 0 192.168.0.100:/var/nfs /mnt/nfs/var/nfs nfs rw,sync,hard,intr 0 0 |
Instead of rw,sync,hard,intr you can use different mount options. To learn more about available options, take a look at
man nfs
To test if your modified /etc/fstab is working, reboot the client:
reboot
After the reboot, you should find the two NFS shares in the outputs of
df -h
client:~# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 30G 748M 27G 3% /
tmpfs 63M 0 63M 0% /lib/init/rw
udev 10M 52K 10M 1% /dev
tmpfs 63M 0 63M 0% /dev/shm
192.168.0.100:/home 30G 764M 27G 3% /mnt/nfs/home
192.168.0.100:/var/nfs
30G 764M 27G 3% /mnt/nfs/var/nfs
client:~#
and
mount
client:~# mount
/dev/sda1 on / type ext3 (rw,errors=remount-ro)
tmpfs on /lib/init/rw type tmpfs (rw,nosuid,mode=0755)
proc on /proc type proc (rw,noexec,nosuid,nodev)
sysfs on /sys type sysfs (rw,noexec,nosuid,nodev)
udev on /dev type tmpfs (rw,mode=0755)
tmpfs on /dev/shm type tmpfs (rw,nosuid,nodev)
devpts on /dev/pts type devpts (rw,noexec,nosuid,gid=5,mode=620)
192.168.0.100:/home on /mnt/nfs/home type nfs (rw,sync,hard,intr,addr=192.168.0.100)
192.168.0.100:/var/nfs on /mnt/nfs/var/nfs type nfs (rw,sync,hard,intr,addr=192.168.0.100)
client:~#
7 Links
- Linux NFS: http://nfs.sourceforge.net
- Debian: http://www.debian.org
