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Linux: How To Setup AutoFS

Installing AutoFS on Ubuntu Desktop 10.04.1

I followed most of the instructions here:

https://help.ubuntu.com/community/Autofs

First, install this on the client:

# apt-get install -y autofs

Edit the /etc/auto.masterfile:

/home /etc/auto.home

+auto.master

which means for the local mount point /home, use the /etc/auto.homeconfig file.

Then edit /etc/auto.home:

* my-nfs-server:/home/&

Unmount static mounts (if any) and edit /etc/fstab (if any):

$ sudo umount /server

Remove (or comment out) their respective entries in /etc/fstab.

#server:/ /server/ nfs defaults 0 0

Reload autofs:

# /etc/init.d/autofs reload

How to test that it works:

1. Create a user on the NFS server with a home directory. Create a test file like test-nfs.txt.

2. Create the same user (without a home dir) on the NFS client with the same user ID andgroup ID (required).

3. Create a password for the new user on the NFS client.4. Log into the NFS client as the new user and list files to see your test file.5. This also works when you log in as the new user from the Ubuntu GUI login screen.

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Another AutoFS example configuration

Client

/etc/auto.master:

/nfs/home /etc/auto.home

+auto.master

/etc/auto.home:

* nfs-server:/nfs/home/&

Even simpler, minimal AutoFS example configuration

Client

/etc/auto.master:

/nfs /etc/auto.nfs

+auto.master

/etc/auto.nfs:

* nfs-server:/nfs/ service autofs restart

autofs start/running, process XXXXX

=====================================================================================

Mounting NFS File Systems using autofs

A third option for mounting an NFS share is the use of the autofs service. Autofsuses the automount

daemon to manage your mount points by only mounting them dynamically when they are accessed.

Autofsconsults the master map configuration file /etc/auto.masterto determine which mount

points are defined. It then starts an automount process with the appropriate parameters for each

mount point. Each line in the master map defines a mount point and a separate map file that defines thefile systems to be mounted under this mount point. For example, the /etc/auto.miscfile might

define mount points in the /miscdirectory; this relationship would be defined in the

/etc/auto.masterfile.

Each entry in auto.masterhas three fields. The first field is the mount point. The second field is the

location of the map file, and the third field is optional. The third field can contain information such as a

timeout value.

For example, to mount the directory /proj52on the remote machine penguin.example.net at the

mount point /misc/myprojecton your machine, add the following line to auto.master:

/misc /etc/auto.misc --timeout 60

Next, add the following line to /etc/auto.misc:

myproject -rw,soft,intr,rsize=8192,wsize=8192 penguin.example.net:/proj52

The first field in /etc/auto.miscis the name of the /miscsubdirectory. This subdirectory is created

dynamically by automount. It should not actually exist on the client machine. The second field contains

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mount options such as rwfor read and write access. The third field is the location of the NFS export

including the hostname and directory.

Note

The directory /miscmust exist on the local file system. There should be no subdirectories in/miscon

the local file system.

To start the autofs service, at a shell prompt, type the following command:

/sbin/service autofs restart

To view the active mount points, type the following command at a shell prompt:

/sbin/service autofs status

If you modify the /etc/auto.masterconfiguration file while autofs is running, you must tell the

automount daemon(s) to reload by typing the following command at a shell prompt:

/sbin/service autofs reload

=======================================================================

HOWTO Setup autofs on Fedora

With autofs, the file systems are mounted as required or on demand, and then automaticallyunmounted when they have not been used for some time. This means you can have two machines

both of which mount file systems from the other and the order you boot them does notmatter as long as the remote system is not required during the boot.

Before we begin you will need a machine that is exporting some shares over NFS so see myHOWTO install NFS on Fedorapage for getting that setup first. I'll wait.

So now you know how to setup NFS and get some directories shared.

Installing the software on Fedora is as easy as any other with yum.

sudo yum install autofs

That will also install a number of configuration files into /etc and one in /etc/sysconfig.

To set up a the automounts for the NFS shares being exported by a server we need to edit the file/etc/auto.master adding one line. Using the shares from a machine called linux32. we will bemounting them locally in /net/linux32/

with a 10 minute (600 second) time out.

sudo nano /etc/auto.master

http://blogging.dragon.org.uk/index.php/mini-howtos/howto-install-nfs-of-fedorahttp://blogging.dragon.org.uk/index.php/mini-howtos/howto-install-nfs-of-fedorahttp://blogging.dragon.org.uk/index.php/mini-howtos/howto-install-nfs-of-fedora

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/etc/auto.master

/net/linux32 /etc/auto.nfslinux32 --timeout=600

The file in the middle does not exist, yet, we are about to create it.

sudo nano /etc/auto.nfslinux32

/etc/auto.nfslinux32

home -fstype=nfs,rsize=32768,wsize=32768,intr,tcp,noatime linux32:/home

You will need a line similar to the one above for each share from linux32. The magic ofautomounting is that you do not need to create all the local mount point directories yourself. they

will be created and deleted as necessary. The entry in auto.master will create the first two

directories /net and /net/linux32.

To explain the layout of auto.nfslinux32. The first parameter is the mount point on the localmachine. In this case home which means you will access the fs via /net/linux32/home. The next

parameter -fstype gives the mounting options note it is an fs type of 'nfs'.

The remaining options are from mount and fstab. Take a look at the man pages you may not

want to use these.

Make sure that the autofs service will startup at boot time. If not set it so it will.

sudo chkconfig --list autofs

autofs 0:off 1:off 2:on 3:on 4:on 5:on 6:off

sudo chkconfig autofs on

Start, stop and reload the files for autofs without rebooting using the usual service command.

sudo service autofs status

sudo service autofs stop

sudo service autofs start

sudo service autofs restart

sudo service autofs reload

Very similar automounting will be done automatically when the mount point starts with /net. Ifound there were a few annoyances using the automatic configuration so I do the above.

You may like to turn on the browse mode. This does have one downside in that it means that the

auto mounts will be mounted each time you access the root directory where they are mounted.

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Edit the file /etc/sysconfig/autofs changing the BROWSE_MODE flag to "yes" and reloading

autofs

/etc/sysconfig/autofs

sudo nano /etc/sysconfig/autofs

sudo service autofs reload

Further reading

1. Man pages for autofs, auto.master, mount, umount, nfs2. The mount & umount commands, how to mount stuff and it's options and get it unmounted

again.

3. /etc/fstab how to mount file systems automatically at boot time4. a href="http://blogging.dragon.org.uk/index.php/mini-howtos/howto-install-nfs-of-

fedora">HOWTO install NFS on Fedora

5. /etc/hosts file IP lookups6. /etc/hosts.allow and /etc/hosts.deny A bit of security7. Setting up Samba/Cifs