Hi Guys
I just wondering if there is a way to block ports like 80,21,22 on my routerboard because I am getting ready to hand out public real world IP’s and I dont want customers to have them ports open whats the script to do that with?
Yes. The wiki has lots and lots of firewall examples.
The basic idea is to somehow determine that the destination is a customer - this can be done by out-interface or dst-address - and then drop packet to those ports. Assuming that your customers have IPs in the range of 1.1.1.1/24 that could be
/ip firewall filter
add chain=forward dst-address=1.1.1.1 protocol=tcp dst-port=21,80 action=drop
But why not let your customers run services? That would set you apart from other service providers.
Do check the wiki - lots of articles there. What you are asking is extremely basic a question.