NFS Services Administrator's Guide (B.11.31.03) August 2008

the remount mount option to mount the directory read/write without unmounting
it. See “Changing the Default Mount Options” (page 55)“Changing the Default
Mount Options” on page 51.
If you are logged in as root to the NFS client, check the share permissions to
determine whether root access to the directory is granted to your NFS client.
□ If you are logged in as root to the NFS client, and your client is not allowed root
access to the exported directory, check the passwd database on the NFS server to
determine whether it contains an entry for user nobody. Without root access, the
root user on an NFS client is given the access permissions of an anonymous user.
Also, check whether anonymous users are denied access to the directory (with the
anon=65535 export option).
If your client is not allowed root access or anonymous user ID access to the exported
directory, log in as a non-root user to get access to the directory.
□ If you were attempting to run a program when you received the “permission
denied” message, enter the ls -l command on the NFS server to check whether
the program you tried to run has the setuid bit set. If it does, check /etc/fstab
to determine whether the directory was mounted with the nosuid mount option.
If necessary, remove the nosuid option from the /etc/fstab file, then unmount
and remount the directory.
“Device Busy” Message
□ If you received the “device busy” message while attempting to mount a
directory, check whether it is already mounted.
□ 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. Enter 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, enter the following
command:
/usr/sbin/fuser -ck local_mount_point
3. Try again to unmount the directory.
132 Troubleshooting NFS Services