Hi,
I don’t understand what you try to achieve.
If you have correct firewall rules before your last deny rule, you should be fine.
If you’re using winbox, make sure, you display the rules in the order, they will be applied.
To ensure this, you need to click on the “#” column in Winbox.
Regards,
Ape
First, you should update RouterOS, 6.34 is very old and many security loopholes.
Then, there are different chains in the firewall, input, forward and output. The ones you want to focus is input (to the router) and forward (through the router)
Below samples of “Drop All” rules for input and forward chains:
/ip firewall filter
add action=drop chain=forward comment="Forward Chain Default Drop Rule"
add action=drop chain=input comment="Input chain Default Drop Rule"