:local num [/system script get num source]
:local count [:len [/interface  l2tp-client find ]]
:local pnum 0

:set pnum ($num+1)
/system script set num source="$pnum"

:if ($num>$count) do={
    :set num 1
    /system script set num source="1"
}

/ip firewall mangle add action=mark-routing chain=prerouting new-routing-mark="r$num" src-address=$"remote-address"

:local localips [/ip address get [/ip address find interface="l2tp-out$num"] address ]
:local localip [:pick $"localips" begin=0 end=([:find $"localips" "/"])]

/tool fetch url="http://192.168.250.250:18702/server/ros/up/ip/$localip" mode=http
/file remove "$localip"