# Default Filter Rules - MikroTik Script RouterOS

    Default Filter rules mikrotik after installation or after reset

    /ip firewall filter
    add action=accept chain=input comment=\
        "defconf: accept established,related,untracked" connection-state=\
        established,related,untracked
    add action=drop chain=input comment="defconf: drop invalid" connection-state=\
        invalid
    add action=accept chain=input comment="defconf: accept ICMP" protocol=icmp
    add action=accept chain=input comment=\
        "defconf: accept to local loopback (for CAPsMAN)" dst-address=127.0.0.1
    add action=drop chain=input comment="defconf: drop all not coming from LAN" \
        in-interface-list=!LAN
    add action=accept chain=forward comment="defconf: accept in ipsec policy" \
        ipsec-policy=in,ipsec
    add action=accept chain=forward comment="defconf: accept out ipsec policy" \
        ipsec-policy=out,ipsec
    add action=accept chain=forward comment=\
        "defconf: accept established,related, untracked" connection-state=\
        established,related,untracked
    add action=drop chain=forward comment="defconf: drop invalid" \
        connection-state=invalid
    add action=drop chain=forward comment=\
        "defconf: drop all from WAN not DSTNATed" connection-nat-state=!dstnat \
        connection-state=new in-interface-list=WAN
    Credit:	www.o-om.com