DEBIAN SETUP

Make sure you have NFS server support in your server’s kernel (kernel module named “knfsd.ko” under your /lib/modules/uname -r/ directory structure)

$ grep NFSD /boot/config-`uname -r`

or similar (wherever you’ve stashed your config file, for example, perhaps in /usr/src/linux/.config.)

There are at ltwo mainstream NFS server implementations that people use (excluding those implemented in Python and similar): one implemented in user space, which is slower however easier to debug, and the other implemented in kernel space, which is faster. Below shows the setup of the kernel-space one. If you wish to use the user-space server, then install the similarly-named package.

First, the packages to begin with:

1.  $ aptitude install nfs-kernel-server portmap

Note that portmap defaults to only listening for NFS connection attempts on 127.0.0.1 (localhost), so if you wish to allow connections on your local network, then you need to edit /etc/default/portmap, to comment out the “OPTIONS” line. Also, we need to ensure that the /etc/hosts.allow file allows connections to the portmap port. For example:

2.   Now run the following commands. This will edit the portmap configuration file and all
the subnet in your hosts.allow for which ever subnet is nfs server is on

•           $ perl -pi -e ‘s/^OPTIONS/#OPTIONS/’ /etc/default/portmap
•           $ echo “portmap: 192.168.1.” >> /etc/hosts.allow
•           $ /etc/init.d/portmap restart 
•           $ echo “rpcbind: ALL” >> /etc/hosts.allow
  

See ‘man hosts.allow’ for examples on the syntax. But in general, specifying only part of the IP address like this (leaving the trailing period) treats the specified IP address fragment as a wildcard, allowing all IP addresses in the range 192.168.1.0 to 192.168.1.255 (in this example.) You can do more “wildcarding” using DNS names, and so on too.

3. Then, edit the /etc/exports file, which lists the server’s filesystems to export over NFS to client machines. The following example shows the addition of a line which adds the path “/example”, for access by any machine on the local network (here 192.168.1.*).

4.  $ echo “/example 192.168.1.0/255.255.255.0(rw,no_root_squash,subtree_check)” >> /etc/exports
5.  $ /etc/init.d/nfs-kernel-server reload

This tells the server to serve up that path, readable/writable, with root-user-id connecting clients to use root access instead of being mapped to ‘nobody’, and to use the ‘subtree_check’ to silence a warning message. Then, reloads the server.

6. On the Client server you wish to mount to the NFS share type the following

• $ mount 192.168.1.100:/example /mnt/example

Result should look like this if you type

• $mount <enter>

/dev/sda3 on / type ext4 (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)
/dev/sda1 on /tmp type ext4 (rw)
rpc_pipefs on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw)
nfsd on /proc/fs/nfsd type nfsd (rw)
192.168.1.100:/nicktest on /mnt/nfs type nfs (rw,nolock,addr=192.168.1.100)