NFS Configuration on Linux RHEL/CentOS 6

                                            NFS (NETWORK FILE SYSTEM)

       

          

   NFS (Network File System) is used to sharing the files and folders between linux to unix and unix to linux machines,NFS was  developed by Sun Mycro Systems in the year 1984.
 

Features: 

      1. Every one can access same data.

      2. Reduce Storage Cost and Easy to use.

      3. Centralized Management of Files.

      4. Secured with Firewalls and Kerberos.

NFS Configuration : 

·                      NFS Port Number      :    2049

·                      Service Name            :    nfs

·                      Packages                   :    nfs-utils & nfs-utils-lib

·                      /etc/exports  :  It is main Configuration file of NFS, define all                        exported files and folders in this path. 

·                      /etc/sysconfig/nfs  :  It is also Configuration file of NFS to controle on which port rpc and other services are listening.

To setup NFS Server, we have at least two Linux Machines.In this article we will be using two machines, one is NFS Server and  another one is NFS Client
     

              NFS Server    :    192.168.0.99

              NFS Client      :   192.168.0.20


                         Server Side Configuration(192.168.0.99)

 Configure Server machine (192.168.0.99) using below steps

Step 1:  Install NFS Packages & start services

Install NFS Packages using yum command

   [root@bsrtech ~]# yum install  nfs-utils nfs-utils-lib -y
start nfs service

   [root@bsrtech ~]# service nfs start

   [root@bsrtech ~]# chkconfig nfs on

   (By using chkconfig for every reboot this services automatically starts)

 

Step 2 : Configure Shared Folders

      

     [root@bsrtech ~]# vim /etc/exports

      syntax :  
      
         ex  : /nfsdata  192.168.0.20(rw,sync)

      save&quit(:wq)

 where  

    rw    :  read & write permissions of /nfsdata folder
   sync : sync confirms requests to the shared directory only once the changes have  been  committed.

After changes , restart service
    
   [root@bsrtech ~]# service  nfs  restart
 By default kernel will read root_squash means anyone who wants to access /nfsdata comes under others.So we have to change permissions of /data as readwrite to others.
   [root@bsrtech ~]# chmod 777 /nfsdata


Note : By giving like this there is no security and any file created by users under /nfsdata should get the owner and group ownership to nfsnobody.
 

To prevent this one provide no_root_squash in /etc/exports

   [root@bsrtech ~]# vim /etc/exports

       /nfsdata  192.168.0.20(rw,sync,no_root_squash)

       save&quit (:wq)

Change permissons of /nfsdata folder

 [root@bsrtech ~]# chmod 750 /nfsdata

 [root@bsrtech ~]# service nfs restart

Create some files in shared directory

 [root@bsrtech ~]# cd /nfsdata

 [root@bsrtech nfsdata]# touch f1 f2 f3 f4


                                         Client Side Configuration (192.168.0.20)

  
Configure Client machine (192.168.0.20) using below steps

 Step 1: Install NFS Packages & start NFS service

    Install NFS Packages using yum command

 [root@nfsclient ~]# yum install  nfs-utils nfs-utils-lib -y

  [root@nfsclient ~]# service nfs start

  [root@nfsclient ~]# chkconfig nfs on

Step2 : To findout which files or directories are                            exported from the server 
  

  [root@nfsclient ~]# showmount -e 192.168.0.99

   where 192.168.0.99 is server ip address

 Step3 : Mount shared NFS Directory
   

  Mount Sahred NFS directory using mount command, first create folder for mount point

   [root@nfsclient ~]# mkdir /mnt/nfsdata 

   [root@nfsclient ~]# mount -t nfs 192.168.0.99:/nfsdata   /mnt/nfsdata

   Verify above mount point using mount command

   [root@nfsclient ~]# mount


 The above mount command mounted the  nfs shared directory on to nfs client on temporarily, to mount permanently write in /etc/fstab see below

   [root@nfsclient ~]# vim /etc/fstab

     192.168.0.99:/nfsdata /mnt/nfsdata  nfs defauls 0 0


step 4 : Check the shared files & folders


    Move to shared mounted directory    

   [root@nfsclient ~]# cd /mnt/nfsdata

   [root@nfsclient nfsdata]# ls

       f1  f2  f3  f4  

   (these are shared files from nfs server machine)