Beyond Linux® From Scratch - Version 6.3

Chapter 19. Major Servers

NFS Utilities-1.1.2

Introduction to NFS Utilities

The NFS Utilities package contains the userspace server and client tools necessary to use the kernel's NFS abilities. NFS is a protocol that allows sharing file systems over the network.

Package information

NFS Utilities Dependencies

Required

portmap-6.0 (Runtime dependency)

Optional

TCP Wrapper-7.6

Optional for NFSv4 Support

pkg-config-0.22, libevent, and libnsfidmap

Optional for GSS (RPC Security) Support

pkg-config-0.22, MIT Kerberos V5-1.6 or Heimdal-1.1 or libgssapi, and librpcsecgss

Optional for SPKM-3 Support

SPKM-3

User Notes: http://wiki.linuxfromscratch.org/blfs/wiki/nfs-utils

Kernel Configuration

Enable the following options in the kernel configuration and recompile the kernel if necessary: 

File systems:
  Network File Systems:
    NFS File System Support: M or Y
    NFS Server Support: M or Y

Select the appropriate sub-options that appear when the above options are selected.

Installation of NFS Utilities

Before you compile the program, ensure that the nobody user and nogroup group have been created. You can add them by running the following commands as the root user: 

groupadd -g 99 nogroup &&
useradd -c "Unprivileged Nobody" -d /dev/null -g nogroup \
    -s /bin/false -u 99 nobody
[Note]

Note

The classic uid and gid values are 65534 which is also -2 when interpreted as a signed 16-bit number. These values impact other files on some filesystems that do not have support for sparse files. The nobody and nogroup values are relatively arbitrary. The impact on a server is nil if the exports file is configured correctly. If it is misconfigured, an ls -l or ps listing will show a uid or gid number of 65534 instead of a name. The client uses nobody only as the user running rpc.statd.

Install NFS Utilities by running the following commands: 

./configure --prefix=/usr \
            --sysconfdir=/etc \
            --disable-nfsv4 \
            --disable-gss &&
make

If your /usr directory is NFS mounted, you should install the executables in /sbin by passing an additional parameter --sbindir=/sbin to the above ./configure command.

This package does not come with a test suite.

Now, as the root user: 

make install

Command Explanations

--disable-nfsv4: Disables support for NFS version 4.

--disable-gss: Disables support for RPCSEC GSS (RPC Security).

Configuring NFS Utilities

Server Configuration

/etc/exports contains the exported directories on NFS servers. Refer to the exports.5 manual page for the syntax of this file. Also refer to the "NFS HowTo" available at http://nfs.sourceforge.net/nfs-howto/ for information on how to configure the servers and clients in a secure manner. For example, for sharing the /home directory over the local network, the following line may be added: 

/home <192.168.0.0/255.255.255.0>(rw,subtree_check,anonuid=99,anongid=99)
Boot Script

Install the /etc/rc.d/init.d/nfs-server init script included in the blfs-bootscripts-20080816 package to start the server at boot. 

make install-nfs-server

Now create the /etc/sysconfig/nfs-server configuration file: 

cat > /etc/sysconfig/nfs-server << "EOF"
PORT="2049"
PROCESSES="8"
QUOTAS="no"
KILLDELAY="10"
EOF
tcpwrappers Configuration

If you have TCP Wrapper-7.6 installed and there is a restrictive /etc/hosts.deny file, ensure you have an entry in the /etc/hosts.allow file for access from the portmap daemon. See the man page in section 5 for hosts_access for details on creating appropriate rules.

Client Configuration

/etc/fstab contains the directories that are to be mounted on the client. Alternately the partitions can be mounted by using the mount command with the proper options. To mount the /home and /usr partitions, add the following to the /etc/fstab: 

<server-name>:/home  /home nfs   rw,_netdev,rsize=8192,wsize=8192 0 0
<server-name>:/usr   /usr  nfs   ro,_netdev,rsize=8192            0 0
Boot Script

Install the /etc/rc.d/init.d/nfs-client init script included in the blfs-bootscripts-20080816 package to start the client services at boot. 

make install-nfs-client

To automatically mount nfs filesystems, clients will also need to install the netfs bootscript as described in Configuring for Network Filesystems.

Contents

Installed Programs: exportfs, mount.nfs, mount.nfs4, nfsstat, rpc.mountd, rpc.nfsd, rpc.statd, rpcdebug, showmount, sm-notify, start-statd and umount.nfs as well as umount.nfs4
Installed Libraries: None
Installed Directories: /var/lib/nfs

Short Descriptions

exportfs

maintains a list of NFS exported file systems.

mount.nfs

Used to mount a network share using NFS

mount.nfs4

Used to mount a network share using NFSv4

nfsstat

prints NFS statistics.

rpc.mountd

implements the NFS mount protocol on an NFS server.

rpc.nfsd

implements the user level part of the NFS service on the server.

rpc.statd

is used by the NFS file locking service. Run on both sides, client as well as server, when you want file locking enabled.

rpcdebug

sets or clears the kernel's NFS client and server debug flags.

showmount

displays mount information for an NFS server.

sm-notify

is used to send Network Status Monitor reboot messages.

start-statd

is a script called by nfsmount when mounting a filesystem with locking enabled, if statd does not appear to be running. It can be customised with whatever flags are appropriate for the site.

umount.nfs

Used to unmount a network share using NFS

umount.nfs4

Used to unmount a network share using NFSv4

Last updated on 2008-05-09 08:00:42 -0500