In this blog I will show you how to make voucher codes of 5-6 characters, I found the instructions at the PFsense community forum so all the credits goes to them.
First you need to generate new Voucher Public Key and Voucher Private Key, you need to access the shell command of PFsense then typing the following commands:
openssl genrsa 30 > key.private
openssl rsa -pubout < key.private >key.public
Then you have to get the actual keys, by typing the following commands:
Now you have to input the keys for both Voucher Public Key and Voucher Private Key, double check your work they should match perfectly!
Then change the following:
# of Roll bits = 6
# of Ticket bits = 16
# of Checksum bits = 6
Then save and generate new 5-6 character of vouchers.