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authorGravatar Christian Hesse <mail@eworm.de>2023-03-07 10:57:42 +0100
committerGravatar Christian Hesse <mail@eworm.de>2023-03-07 22:26:01 +0100
commita832fd04ef085ef7e85000843a8e8fa59ce36dfb (patch)
treec977ca4b5167d8aa07dbe6bfe15fca8f467db0d9 /dhcp-to-dns.rsc
parent1e6e0646e256c4acb9f8470853d0699286af010e (diff)
rename scripts and add file extension ".rsc"change-95
No functional change for the user... The migration is done automatically.
Diffstat (limited to 'dhcp-to-dns.rsc')
-rw-r--r--dhcp-to-dns.rsc97
1 files changed, 97 insertions, 0 deletions
diff --git a/dhcp-to-dns.rsc b/dhcp-to-dns.rsc
new file mode 100644
index 0000000..48f96b2
--- /dev/null
+++ b/dhcp-to-dns.rsc
@@ -0,0 +1,97 @@
+#!rsc by RouterOS
+# RouterOS script: dhcp-to-dns
+# Copyright (c) 2013-2023 Christian Hesse <mail@eworm.de>
+# https://git.eworm.de/cgit/routeros-scripts/about/COPYING.md
+#
+# provides: lease-script, order=20
+#
+# check DHCP leases and add/remove/update DNS entries
+# https://git.eworm.de/cgit/routeros-scripts/about/doc/dhcp-to-dns.md
+
+:local 0 "dhcp-to-dns";
+:global GlobalFunctionsReady;
+:while ($GlobalFunctionsReady != true) do={ :delay 500ms; }
+
+:global Domain;
+:global HostNameInZone;
+:global Identity;
+:global PrefixInZone;
+:global ServerNameInZone;
+
+:global CharacterReplace;
+:global IfThenElse;
+:global LogPrintExit2;
+:global ScriptLock;
+
+$ScriptLock $0 false 10;
+
+:local Zone \
+ ([ $IfThenElse ($PrefixInZone = true) "dhcp." ] . \
+ [ $IfThenElse ($HostNameInZone = true) ($Identity . ".") ] . $Domain);
+:local Ttl 5m;
+:local CommentPrefix ("managed by " . $0 . " for ");
+:local CommentString ("--- " . $0 . " above ---");
+
+:if ([ :len [ /ip/dns/static/find where comment=$CommentString name=- type=NXDOMAIN disabled ] ] = 0) do={
+ /ip/dns/static/add comment=$CommentString name=- type=NXDOMAIN disabled=yes;
+ $LogPrintExit2 warning $0 ("Added disabled static dns record with comment '" . $CommentString . "'.") false;
+}
+:local PlaceBefore ([ /ip/dns/static/find where comment=$CommentString name=- type=NXDOMAIN disabled ]->0);
+
+:foreach DnsRecord in=[ /ip/dns/static/find where comment ~ $CommentPrefix ] do={
+ :local DnsRecordVal [ /ip/dns/static/get $DnsRecord ];
+ :local MacAddress [ $CharacterReplace ($DnsRecordVal->"comment") $CommentPrefix "" ];
+ :if ([ :len [ /ip/dhcp-server/lease/find where mac-address=$MacAddress address=($DnsRecordVal->"address") status=bound ] ] > 0) do={
+ $LogPrintExit2 debug $0 ("Lease for " . $MacAddress . " (" . $DnsRecordVal->"name" . ") still exists. Not deleting DNS entry.") false;
+ } else={
+ :local Found false;
+ $LogPrintExit2 info $0 ("Lease expired for " . $MacAddress . " (" . $DnsRecordVal->"name" . "), deleting DNS entry.") false;
+ /ip/dns/static/remove $DnsRecord;
+ }
+}
+
+:foreach Lease in=[ /ip/dhcp-server/lease/find where status=bound ] do={
+ :local LeaseVal;
+ :do {
+ :set LeaseVal [ /ip/dhcp-server/lease/get $Lease ];
+ } on-error={
+ $LogPrintExit2 debug $0 ("A lease just vanished, ignoring.") false;
+ }
+
+ :if ([ :len ($LeaseVal->"address") ] > 0) do={
+ :local Comment ($CommentPrefix . $LeaseVal->"mac-address");
+ :local HostName [ $IfThenElse ([ :len ($LeaseVal->"host-name") ] = 0) \
+ [ $CharacterReplace ($LeaseVal->"mac-address") ":" "-" ] \
+ [ $CharacterReplace ($LeaseVal->"host-name") " " "" ] ];
+
+ :local Fqdn ($HostName . "." . [ $IfThenElse ($ServerNameInZone = true) ($LeaseVal->"server" . ".") ] . $Zone);
+ :local DnsRecord [ /ip/dns/static/find where name=$Fqdn ];
+ :if ([ :len $DnsRecord ] > 0) do={
+ :local DnsIp [ /ip/dns/static/get $DnsRecord address ];
+
+ :local DupMacLeases [ /ip/dhcp-server/lease/find where mac-address=($LeaseVal->"mac-address") status=bound ];
+ :if ([ :len $DupMacLeases ] > 1) do={
+ :set ($LeaseVal->"address") [ /ip/dhcp-server/lease/get ($DupMacLeases->([ :len $DupMacLeases ] - 1)) address ];
+ }
+
+ :if ([ :len ($LeaseVal->"host-name") ] > 0) do={
+ :local HostNameLeases [ /ip/dhcp-server/lease/find where host-name=($LeaseVal->"host-name") status=bound ];
+ :if ([ :len $HostNameLeases ] > 1) do={
+ :set ($LeaseVal->"address") [ /ip/dhcp-server/lease/get ($HostNameLeases->0) address ];
+ }
+ }
+
+ :if ($DnsIp = $LeaseVal->"address") do={
+ $LogPrintExit2 debug $0 ("DNS entry for " . $Fqdn . " does not need updating.") false;
+ } else={
+ $LogPrintExit2 info $0 ("Replacing DNS entry for " . $Fqdn . ", new address is " . $LeaseVal->"address" . ".") false;
+ /ip/dns/static/set name=$Fqdn address=($LeaseVal->"address") ttl=$Ttl comment=$Comment $DnsRecord;
+ }
+ } else={
+ $LogPrintExit2 info $0 ("Adding new DNS entry for " . $Fqdn . ", address is " . $LeaseVal->"address" . ".") false;
+ /ip/dns/static/add name=$Fqdn address=($LeaseVal->"address") ttl=$Ttl comment=$Comment place-before=$PlaceBefore;
+ }
+ } else={
+ $LogPrintExit2 debug $0 ("No address available... Ignoring.") false;
+ }
+}