DDNS Script for(changeip.com) Mikrotik.

# Define User Variables
:global ddnsuser "USERNAME"
:global ddnspass "PASS"
:global ddnshost "DOMAIN NAME"

# Define Global Variables
:global ddnsip
:global ddnslastip
:if ([ :typeof $ddnslastip ] = nil ) do={ :global ddnslastip "0" }

:global ddnsinterface
:global ddnssystem ("mt-" . [/system package get system version] )

# Define Local Variables
:local int

# Loop thru interfaces and look for ones containing
# default gateways without routing-marks
:foreach int in=[/ip route find dst-address=0.0.0.0/0 active=yes ] do={ 
  :if ([:typeof [/ip route get $int routing-mark ]] != str ) do={
     :global ddnsinterface [/ip route get $int interface]
  } 
}

# Grab the current IP address on that interface.
:global ddnsip [ /ip address get [/ip address find interface=$ddnsinterface ] address ]

# Did we get an IP address to compare?
:if ([ :typeof $ddnsip ] = nil ) do={
   :log info ("DDNS: No ip address present on " . $ddnsinterface . ", please check.")
} else={

  :if ($ddnsip != $ddnslastip) do={

    :log info "DDNS: Sending UPDATE!"
    :log info [ :put [/tool dns-update name=$ddnshost address=[:pick $ddnsip 0 [:find $ddnsip "/"] ] key-name=$ddnsuser key=$ddnspass ] ]
    :global ddnslastip $ddnsip

  } else={ 
    :log info "DDNS: No update required."
  }

}

# End of script