uname -a

Linux xxxxxxxxxx 2.6.32-696.16.1.el6.x86_64 #1 SMP Wed Nov 15 14:30:01 PST 2017 x86_64 x86_64 x86_64 GNU/Linux
#

cat /etc/redhat-release

Red Hat Enterprise Linux Server release 6.8 (Santiago)

As root
df -h list all the file systems including these:
/dev/mapper/dtfe84_db_dg-lv_dtfe84_db
1.4T 198M 1.3T 1% /dtfe84/dtfe84_db
/dev/mapper/dtfe84_re_dg-lv_dtfe84_rd
7.7G 146M 7.2G 2% /dtfe84/dtfe84_rd
/dev/mapper/dtfe84_tmp_dg-lv_dtfe84_tmp
93G 188M 88G 1% /dtfe84/dtfe84_tmp
/dev/mapper/dtfe84_bkp_dg-lv_dtfe84_bk
769G 197M 730G 1% /dtfe84/dtfe84_bk
/dev/mapper/dtfe83_db_dg-lv_dtfe83_db
385G 195M 365G 1% /dtfe83/dtfe83_db
/dev/mapper/dtfe83_redg-lv_dtfe83_rd
7.7G 146M 7.2G 2% /dtfe83/dtfe83_rd
/dev/mapper/dtfe83_tmp_dg-lv_dtfe83_tmp
25G 173M 23G 1% /dtfe83/dtfe83_tmp
/dev/mapper/dtfe83_bkp_dg-lv_dtfe83_bk_tmp
193G 188M 183G 1% /dtfe83/dtfe83_bk
netappbnt01b:/vol/olapshr_pgfc1i_dr
200G 139G 62G 70% /olapshr/pgfc1i

when I switch to oracle, only these file systems are giving errors

root# su oracle
[oracle]$ df -h
df:

/dtfe84/dtfe84_db': Permission denied

df:

/dtfe84/dtfe84_tmp': Permission denied

df:

/dtfe83/dtfe83_db': Permission denied

df:

/dtfe83/dtfe83_tmp': Permission denied

df:

[root]# cat /etc/fstab|grep dtfe
/dev/mapper/dtfe84_db_dg-lv_dtfe84_db /dtfe84/dtfe84_db ext3 defaults 1 2
/dev/mapper/dtfe84_re_dg-lv_dtfe84_rd /dtfe84/dtfe84_rd ext3 defaults 1 2
/dev/mapper/dtfe84_tmp_dg-lv_dtfe84_tmp /dtfe84/dtfe84_tmp ext3 defaults 1 2
/dev/mapper/dtfe84_bkp_dg-lv_dtfe84_bk /dtfe84/dtfe84_bk ext3 defaults 1 2
/dev/mapper/dtfe83_db_dg-lv_dtfe83_db /dtfe83/dtfe83_db ext3 defaults 1 2
/dev/mapper/dtfe83_redg-lv_dtfe83_rd /dtfe83/dtfe83_rd ext3 defaults 1 2
/dev/mapper/dtfe83_tmp_dg-lv_dtfe83_tmp /dtfe83/dtfe83_tmp ext3 defaults 1 2
/dev/mapper/dtfe83_bkp_dg-lv_dtfe83_bk_tmp /dtfe83/dtfe83_bk ext3 defaults 1 2
netappbnt01b:/vol/olapshr_pgfc1i_dr /olapshr/pgfc1i nfs defaults 0 0

ls -ld of all these mount points as root.
drwxr-xr-x 3 root root 4096 Feb 21 18:10 /dtfe84/dtfe84_db
drwxr-xr-x 3 root root 4096 Feb 21 18:12 /dtfe84/dtfe84_rd
drwxr-xr-x 3 root root 4096 Feb 21 18:14 /dtfe84/dtfe84_tmp
drwxr-xr-x 3 root root 4096 Feb 21 18:17 /dtfe84/dtfe84_bk
drwxr-xr-x 3 root root 4096 Feb 21 18:19 /dtfe83/dtfe83_db
drwxr-xr-x 3 root root 4096 Feb 21 18:21 /dtfe83/dtfe83_rd
drwxr-xr-x 3 root root 4096 Feb 21 18:22 /dtfe83/dtfe83_tmp
drwxr-xr-x 3 root root 4096 Feb 21 18:24 /dtfe83/dtfe83_bk
drwxrwxrwx 12 root root 4096 Nov 9 18:36 /olapshr/pgfc1i

ls -ld as oracle :
ls: cannot access /mountpoint/name : Permission denied