Common NFS errors on Linux server

Common NFS errors & solutions:

1."Server Not Responding" Message
2.  "Access Denied" Message
3."Permission Denied" Message
4.  "Device Busy" Message

Error 1: If You Receive an NFS "Server Not Responding" Message

ping the nfs server from client

1.ping "nfs serer name or ip"

2./usr/bin/rpcinfo -p servername

The rpcinfo command should display the following processes:

    * portmap
    * nfs
    * mountd
    * status
    * nlockmgr
    * llockmgr

If any of these processes is not running, follow the below steps:


a.Make sure the /etc/rc.config.d/nfsconf file on the NFS server contains the following lines:

NFS_SERVER=1
START_MOUNTD=1

b.Make sure that the /etc/inetd.conf file on the NFS server does not contain a line to start rpc.mountd. 
If it does, make sure the START_MOUNTD variable in /etc/rc.config.d/nfsconf is set to 0.

c.Issue the following command on the NFS server to start all the necessary NFS processes:

#/sbin/init.d/nfs.server start

Error 2: If You Receive an "Access Denied" Message

a.check the FS is exported or not

#/usr/sbin/showmount -e server_name

(If it is not exported means u have to edit /etc/exports file in NFS server and put the necessary entry and 
then run the command
/usr/sbin/exportfs -a)

Error 3 :If You Receive a "Permission Denied" Message

a.Check the mount options in the /etc/fstab file on the NFS client. A directory you are attempting to write to may have 
been mounted read-only.

b.Issue the ls -l command to check the HP-UX permissions on the server directory and on the client directory 
that is the mount point. You may not be allowed access to the directory.

c.Issue the following command on the NFS server:

/usr/sbin/exportfs

Or, issue the following command on the NFS client:

/usr/sbin/showmount -e server_name

d. Check the export permissions on the exported directory. The directory may have been exported read-only to your client.
The system administrator of the NFS server can use the remount mount 
option to mount the directory read/write without unmounting it

Error 4 : If You Receive a "Device Busy" Message

a.If you received the "device busy" message while attempting to mount a directory, try to access the mounted directory. 
  If you can access it, then it is already mounted.
  
b.If you received the "device busy" message while attempting to unmount a directory, a user or process is currently using the directory. Wait until the process completes, or follow these steps:
 
 1.Issue the following command to determine who is using the mounted directory:

       /usr/sbin/fuser -cu local_mount_point

   The fuser(1M) command will return a list of process IDs and user names that are currently using the directory 
   mounted under local_mount_point. This will help you decide whether to kill the processes or wait for them to complete.

 2. To kill all processes using the mounted directory, issue the following command:

            /usr/sbin/fuser -ck local_mount_point

 3. Try again to unmount the directory