I do not want to use /etc/mtab and mount them under folders I create in /mnt;
1] It's not /etc/mtab
2] You don't have to create directories in /mnt
, you can create them anywhere, even in /media
So, create the directories in /media
(if that is where you want them to be mounted) and make the relevant entries in /etc/fstab
Then the partitions will be mounted to the right places at boot time.