Recently we had an VM Oracle Linux server 6.9 crashed and we have had to rebuild the server from the scratch. This server has a CIFS mount for Oracle database backup. After we re-created the sever with a newer OVA which is on Oracle Linux server 6.10, we could not mount the CIFS share anymore. It gave us the error:
mount: special device <device> doesn not exist
After digging around, we noticed that the FIPS (Federal Information Processing Standards) was enabled. It turned out FIPS would conflict with CIFS mount.
[root@ProdSjli02 ~]$cat /proc/sys/crypto/fips_enabled
After turned FIPS off in grub.conf — changing fips=1 to fips=0, CIFS mount works as before.