A collection of useful Mikrotik Firewall Filter/Rules
/ip firewall filter
add action=drop chain=input comment="drop Invalid connections" connection-state=invalid
add chain=input comment="allow Established connections" connection-state=established
add chain=input comment="allow remote administration from mikrotik office or other whitelists"\
src-address=159.148.147.0/24
add chain=input comment="allow pings ICMP" protocol=icmp
add chain=input comment="Allow DNS requests from LAN. You can add other services like VPN, Proxy, OSPF etc" dst-port=53\
in-interface=!ether-wan src-address=192.168.199.0/24
add action=drop chain=input comment="drop everything else"/ip firewall filter
add action=drop chain=forward comment="Drop Facebook" connection-mark=facebook_connection dst-port=80,443 protocol=tcp src-address-list=!Facebook_Allowed
add action=drop chain=forward comment="Drop Twitter" connection-mark=twitter_connection dst-port=80,443 protocol=tcp src-address-list=!Twitter_Allowed
/ip firewall mangle
add action=mark-connection chain=prerouting comment=Youtube content=youtube dst-port=80,443 new-connection-mark=youtube_connection passthrough=yes protocol=tcp
add action=mark-connection chain=prerouting content=youtube dst-port=80,443 new-connection-mark=youtube_connection protocol=udp
add action=mark-connection chain=prerouting content=googlevideo dst-port=80,443 new-connection-mark=youtube_connection protocol=tcp
add action=mark-connection chain=prerouting content=googlevideo dst-port=80,443 new-connection-mark=youtube_connection protocol=udp
add action=mark-connection chain=prerouting content=youtu.be dst-port=80,443 new-connection-mark=youtube_connection protocol=tcp
add action=mark-connection chain=prerouting content=youtu.be dst-port=80,443 new-connection-mark=youtube_connection protocol=udp
add action=mark-packet chain=prerouting connection-mark=youtube_connection new-packet-mark=youtube_packets passthrough=no
add action=mark-connection chain=prerouting comment=Netflix content=netflix.com new-connection-mark=netflix_connection passthrough=yes port=80,443 protocol=tcp
add action=mark-connection chain=prerouting content=nflxvideo.net new-connection-mark=netflix_connection passthrough=yes port=80,443 protocol=tcp
add action=mark-connection chain=prerouting content=nflxso.net new-connection-mark=netflix_connection passthrough=yes port=80,443 protocol=tcp
add action=mark-packet chain=prerouting connection-mark=netflix_connection new-packet-mark=netflix_packets passthrough=no port=80,443 protocol=tcp
add action=mark-connection chain=prerouting comment=Facebook content=facebook dst-port=80,443 new-connection-mark=facebook_connection passthrough=no protocol=tcp
add action=mark-connection chain=prerouting content=fbcdn.net dst-port=80,443 new-connection-mark=facebook_connection passthrough=no protocol=tcp
add action=mark-connection chain=prerouting comment=Twitter content=twitter dst-port=80,443 new-connection-mark=twitter_connection passthrough=no protocol=tcp
add action=mark-connection chain=prerouting content=twimg.com dst-port=80,443 new-connection-mark=twitter_connection passthrough=no protocol=tcp
/queue simple
add name="YOUTUBE" target=192.168.88.0/24 parent=none packet-marks=youtube_packets priority=8/8 queue=default/default limit-at=0/0 max-limit=50M/50M burst-limit=0/0 burst-threshold=0/0 burst-time=0s/0s bucket-size=0.1/0.1 total-queue=default
add name="NETFLIX" target=192.168.88.0/24 parent=none packet-marks=netflix_packets priority=8/8 queue=default/default limit-at=0/0 max-limit=50M/50M burst-limit=0/0 burst-threshold=0/0 burst-time=0s/0s bucket-size=0.1/0.1 total-queue=default