By default all SysAdminMan VPSs come with port 443 open to allow https access to the web GUI. A really good security tip, where possible, is to restrict this to only IP addresses that need access.
First, whenever making changes to iptables I always temporarily disable them from running at startup. This way if you make an error and lock yourself out the server just needs a restart. You must remember to re-enable at the end!
Disable iptables at startup and copy the existing configuration –
Next list the current inbound rules with their line numbers –
So https access (port 443) is allowed in rule 9. Now we are going to delete this rule –
Now we add in the new rule to allow access to port 443 from a particular IP address. You will want to change the IP address below (188.8.131.52) to be your IP address. You may also want to change the Ethernet interface (venet0) if you are not using a SysAdminMan VPS –
Now check that the rule is working correctly. If it is we can save the current rules and enable them at startup again –