NFS Services Administrator's Guide (762805-001, March 2014)

To unmount a mounted directory and prevent it from being automatically mounted, follow these
steps:
Automatic Unmount
1. To check for any processes accessing the mounted directory, enter the following command:
fuser -cu mounted_directory
2. To kill the processes, enter the following command:
fuser -ck local_mount_point
3. Unmount the filesystem as follows:
/usr/sbin/umount mounted_directory
4. If the unmount fails, use the forcible option to unmount the filesystem:
/usr/sbin/umount -f mounted_directory
5. Verify whether all the directories are unmounted by entering the following command:
mount
The directories that you have unmounted must not be present in the list displayed.
6. If you do not want the directory to be automatically mounted when the system is rebooted,
remove the directory entry from the /etc/fstab file.
Disabling NFS client capability
To disable the NFS client, follow these steps:
1. On the NFS client, enter the following command to get a list of all the mounted NFS filesystems
on the client
/usr/sbin/nfsstat -m
2. For every NFS mounted directory listed by the nfsstat command, enter the following
command to determine whether the directory is currently in use:
/usr/sbin/fuser -cu local_mount_point
This command lists the process IDs and user names of all processes currently using the mounted
directory.
3. To kill all processes that are using the mounted directory, enter the following command:
/usr/sbin/fuser -ck local_mount_point
4. To unmount all NFS mounted directories, enter the following command:
/usr/sbin/umount -aF nfs
5. To disable the NFS client and AutoFS, edit the /etc/rc.config.d/nfsconf file on the
client to set the NFS_CLIENT and AUTOFS variables to 0, as follows:
NFS_CLIENT=0
AUTOFS=0
This prevents the client processes from starting up again when you reboot the client.
6. Enter the following command to disable NFS client capability:
/sbin/init.d/nfs.client stop
For more information, see umount (1M), mount(1M), and fuser(1M).
NFS Client and server transport connections
NFS runs over both UDP and TCP transport protocols. The default transport protocol is TCP. Using
the TCP protocol increases the reliability of NFS filesystems working across WANs and ensures
that the packets are successfully delivered. TCP provides congestion control and error recovery.
NFS over TCP and UDP works with NFS Version 2 and Version 3.
NFS Client and server transport connections 41