Configuring AutoFS

Introduction:

Auto-mounts are mounted only as they are accessed, and are unmounted after a period of inactivity. Because of this, automounting NFS/Samba shares conserves bandwidth and offers better overall performance compared to static mounts via fstab.

Configuration Files:

The configuration is done with the help of 2 files.

1. /etc/auto.master: It is a main configuration file. It holding the mount points.
2. /etc/auto.nfs1:  It  is a mount point file providing the system options for this specific mount point.
3. /etc/auto.misc: To find the mount options and the key associated to the file system. 

Installation:

Vertify whether autofs installed or not

root# rpm -qa autofs

if not installed then install it

root# yum install -y autofs*

Vertify installed version

root# rpm -qa autofs

View list of files releated to autofs

root# rpm -ql autofs

Configuring autofs:

Edit the /etc/auto.master file

root# cd /etc

root# vim /etc/auto.master

/nfs1  /etc/auto.share

+auto.master

Note: Local mount point nfs1 uses the /etc/auto.share config file

Edit the /etc/auto.shares for automount your remote host(1982.168.0.254)

root# vim /etc/auto.share

nfs1 –fstype=nfs 192.168.0.254:/share

Note: above step should follow the syntax as {mount point} {mount point} {location}

Create a directory /nfs1

root# mkdir /nfs1

Restart the autofs service

root# service autofs restart

Check the remote host’s files exists or not(it show empty directory)

root# ls –l /nfs1

But when access the directory with remote hosts directory. It will display all the content of the remote hosts.

root# cd /nfs1

root# ls –ltr share1

Check the service will run at boot time or not

root# chkconfig --list autofs

To start service at boot time:

root# chkconfig autofs on

Verify the service will run at boot time

root# chkconfig --list autofs

automount:

Automout works from an initial mount point (the one found by autofs to start automount) and from a new map describing the features of this initial mount point. The map associated to the automount will hold all required information for mounting the file system automatically (hence the name). This automatic mount is done as soon as someone tries to accesses something in the directory tree starting from the mount point. Next, the file systems are automatically "unmount" after an inactive period (the default time out is 5 minutes).

The default value of several general settings may be changed in the configuration file /etc/sysconfig/autofs.

To change the default time according to our wish then access the /etc/sysconfig/auto file then change the DEFAULT_TIMEOUT=300(default time set by system is 300 seconds i.e. 5 Minutes).

To change default time to 30 seconds

root# vim /etc/sysconfig/auto

DEFAULT_TIMEOUT=30

root# service autofs reload