There are three ways to achieve this.
- Edit your “/etc/fatab”:
# I assumed that disk A is not mounted as the root (/) filesystem. If it is, just ignore lines with disk A.
- Synblic link if disks A and B are mounted elsewhere:
ln -s /path/to/driveA_mountpoint /var/www/
- Use the bind option of “mount” command:
mount -o bind /var/www/ /path/to/driveA_mountpoint