#!rsc by RouterOS # RouterOS script: netwatch-dns # Copyright (c) 2022 Christian Hesse # https://git.eworm.de/cgit/routeros-scripts/about/COPYING.md # # monitor and manage dns/doh with netwatch # https://git.eworm.de/cgit/routeros-scripts/about/doc/netwatch-dns.md :local 0 "netwatch-dns"; :global GlobalFunctionsReady; :while ($GlobalFunctionsReady != true) do={ :delay 500ms; } :global EitherOr; :global LogPrintExit2; :global ParseKeyValueStore; :global ScriptLock; $ScriptLock $0; :if ([ /system/resource/get uptime ] < 5m) do={ $LogPrintExit2 info $0 ("System just booted, giving netwatch some time to settle.") true; } :local DnsServers [ :toarray "" ]; :local DnsFallback [ :toarray "" ]; :local DnsCurrent [ /ip/dns/get servers ]; :foreach Host in=[ /tool/netwatch/find where comment~"dns" disabled=no ] do={ :local HostVal [ /tool/netwatch/get $Host ]; :local HostInfo [ $ParseKeyValueStore ($HostVal->"comment") ]; :if ($HostVal->"status" = "up" && $HostInfo->"disabled" != true) do={ :if ($HostInfo->"dns" = true) do={ :set DnsServers ($DnsServers, $HostVal->"host"); } :if ($HostInfo->"dns-fallback" = true) do={ :set DnsFallback ($DnsFallback, $HostVal->"host"); } } } :if ([ :len $DnsServers ] > 0) do={ :if ($DnsServers != $DnsCurrent) do={ $LogPrintExit2 info $0 ("Updating DNS servers: " . [ :tostr $DnsServers ]) false; /ip/dns/set servers=$DnsServers; /ip/dns/cache/flush; } } else={ :if ([ :len $DnsFallback ] > 0) do={ :if ($DnsFallback != $DnsCurrent) do={ $LogPrintExit2 info $0 ("Updating DNS servers to fallback: " . [ :tostr $DnsFallback ]) false; /ip/dns/set servers=$DnsFallback; /ip/dns/cache/flush; } } } :local DohServer ""; :local DohCurrent [ /ip/dns/get use-doh-server ]; :foreach Host in=[ /tool/netwatch/find where comment~"doh" disabled=no ] do={ :local HostVal [ /tool/netwatch/get $Host ]; :local HostInfo [ $ParseKeyValueStore ($HostVal->"comment") ]; :if ($HostVal->"status" = "up" && $HostInfo->"doh" = true && $HostInfo->"disabled" != true && $DohServer = "") do={ :set DohServer [ $EitherOr ($HostInfo->"doh-url") ("https://" . $HostVal->"host" . "/dns-query") ]; } } :if ($DohServer != "") do={ :if ($DohServer != $DohCurrent) do={ $LogPrintExit2 info $0 ("Updating DoH server: " . $DohServer) false; /ip/dns/set use-doh-server=$DohServer; /ip/dns/cache/flush; } } else={ :if ($DohCurrent != "") do={ $LogPrintExit2 info $0 ("DoH server (" . $DohCurrent . ") is down, disabling.") false; /ip/dns/set use-doh-server=""; /ip/dns/cache/flush; } }