Mikrotik RouterOS script for Ping-based Fast Failover with PPPoE uplinks.

Netwatch.rsc

/interface pppoe-client
set [find name="internet-speedy"] comment="PROVIDER1"
set [find name="internet-biznet"] comment="PROVIDER2"

/ip route
add comment="Force test pings through PROVIDER1" distance=1 dst-address=4.2.2.4/32 gateway=internet-speedy
add comment="Block test pings through other providers" distance=20 dst-address=4.2.2.4/32 type=blackhole

/tool netwatch
add comment=CheckCon down-script=":local \"p1\"  [/interface pppoe-client find c\
    omment=\"PROVIDER1\" default-route-distance!=20];\r\
    \n/interface pppoe-client disable \$p1;\r\
    \n:delay 500ms;\r\
    \n/interface disable [find name=[/interface pppoe-client get \$p1 interface]\
    ];\r\
    \n/interface enable [find name=[/interface pppoe-client get \$p1 interface]]\
    ;\r\
    \n/interface pppoe-client set \$p1 default-route-distance=20 disabled=no;\r\
    \n/interface pppoe-client set [find comment=\"PROVIDER2\" disabled=yes] disa\
    bled=no;\r\
    \n/tool e-mail send to=\"YourEmailAddress\" body=\"Uplink with PROVIDER1 Los\
    t, Switched to PROVIDER2\" subject=\"Lost uplink with PROVIDER1\";\r\
    \n#/ip firewall connection remove [find dst-address!=\"10.0.0.0/8\"];\r\
    \n" host=4.2.2.4 interval=5s timeout=2s up-script=":local \"p1\"  [/interfac\
    e pppoe-client find comment=\"PROVIDER1\" default-route-distance!=1];\r\
    \n:if ([:len \$p1] > 0) do={\r\
    \n  :local \"p1Status\";\r\
    \n  /tool netwatch disable [find comment=\"CheckCon\"];\r\
    \n  /interface pppoe-client disable \$p1;\r\
    \n  :delay 500ms;\r\
    \n  /interface disable [find name=[/interface pppoe-client get \$p1 interfac\
    e]];\r\
    \n  /interface enable [find name=[/interface pppoe-client get \$p1 interface\
    ]];\r\
    \n  /interface pppoe-client set \$p1 default-route-distance=1 disabled=no;\r\
    \n  :do {\r\
    \n    :delay 500ms;\r\
    \n    /interface pppoe-client monitor \$p1 once do={ :set \"p1Status\" \$sta\
    tus };\r\
    \n  } while=(\$p1Status != \"connected\");\r\
    \n\r\
    \n  :local \"pingResult\";\r\
    \n  do {\r\
    \n    :set \"pingResult\" [/ping address=4.2.2.4 count=1 interval=5s];\r\
    \n  } while=(\$pingResult != 1);\r\
    \n  /tool netwatch enable [find comment=\"CheckCon\"];\r\
    \n\r\
    \n  /interface pppoe-client set [find comment=\"PROVIDER2\" disabled=yes] di\
    sabled=no;\r\
    \n  /tool e-mail send to=\"YourEmailAddress\" body=\"Uplink with PROVIDER1 R\
    egained, Switched back to PROVIDER1\" subject=\"Regained uplink with PROVIDE\
    R1\";\r\
    \n  #/ip firewall connection remove [find dst-address!=\"10.0.0.0/8\"];\r\
    \n}\r\
    \n"