Unable to Change Directory to the Mount Point as Root – Permission Denied on HP-UX

Hello… i will show you how to solve the issue of permission denied when you find “permission denied” when trying to change directory to the specific directory. Below is some of the example and already become as root:

# cd /usr/local/sap/tools/
ksh: /usr/local/sap/tools/: permission denied
# ll /usr/local/sap/tools/
/usr/local/sap/tools/ not found
#

when i trying to display all the mountpoints, there were no mountpoint that i want to change to except for /usr, but i believe the abovementioned directory is not using /usr, but must be coming from external network.  On top of that, changing mod to the directory also not working as well as per below example:

# pwd
/usr/local
# chmod 755 sap/
chmod: can’t change sap/: Permission denied

When i see the mounted partition in a working server, i can see the mount point as nfs and imported from nfs server, please see below:

tools-x.xx.xxx.net:/usr/local/sap
4145152 2287273 1741912 57% /usr/local/sap

In order to get clarified, i have to see the properties of exported mount points on the nfs server:

#showmount -e <nfs_server>
export list for <nfs_server>:
/usr/local/sap (everyone)

So, from the above result, i know that mount point should be accessible and mounted by everyone and no issue if we want to mount it from the client side.

Cause

The issue is when i try to mount the nfs on client side, the error show up as device busy:

# mount <nfs_server>:/usr/local/sap /usr/local/sap
nfs mount: /usr/local/sap: Device busy

And i can see the above mount point been mounted:

# mount |grep -i ‘local/sap’
/usr/local/sap on /etc/auto_direct ignore,direct,dev=4000044 on Fri Aug 31 15:49:08 2018

Resolution

This can be resolved by unmount first the partition and mount it back accordingly. You may verify the mount point by using ‘bdf’ command as per below example:

# umount /usr/local/sap; # mount tools-<nfs_server>:/usr/local/sap  /usr/local/sap
# bdf

tools-ent.<nfs_server>:/usr/local/sap
4145152 2287273 1741912 57% /usr/local/sap

Lastly, you also may change directory to the above partition and list down its files without any problem.