routeros-scripts/dhcp-to-dns
2019-02-08 13:03:42 +01:00

76 lines
2.6 KiB
Text

#!rsc
# RouterOS script: dhcp-to-dns
# Copyright (c) 2013-2019 Christian Hesse <mail@eworm.de>
#
# check DHCP leases and add/remove/update DNS entries
:global CharacterReplace;
:global Identity;
:global Domain;
:global HostNameInZone;
:local Zone;
:if ($HostNameInZone = true) do={
:set Zone ("dhcp." . $Identity . "." . $Domain);
} else={
:set Zone ("dhcp." . $Domain);
}
:local Ttl 5m;
:local HostName;
:local Fqdn;
:local DnsIp;
:local DhcpIp;
:local DnsNode;
:local DhcpNode;
:foreach Static in=[ / ip dns static find where name ~ (".*\\." . $Zone) ] do={
:set Fqdn [ / ip dns static get $Static name ];
:set HostName [ :pick $Fqdn 0 ([ :len $Fqdn ] - ([ :len $Zone ] + 1)) ];
:set DhcpNode [ / ip dhcp-server lease find where host-name=$HostName dynamic=yes ];
:if ([ :len $DhcpNode ] > 0) do={
:log debug ("Lease for " . $HostName . " still exists. Not deleting.");
} else={
:local Found false;
:log info ("Lease expired for " . $HostName . ", deleting DNS entry.");
/ ip dns static remove $Static;
}
}
:foreach Lease in=[ / ip dhcp-server lease find where dynamic=yes ] do={
:local Mac [ / ip dhcp-server lease get $Lease mac-address ];
:set DhcpIp [ / ip dhcp-server lease get $Lease address ];
:local Comment ("managed by dhcp-to-dns for " . $Mac);
:set HostName [ $CharacterReplace [ / ip dhcp-server lease get $Lease host-name ] " " "" ];
:if ($HostName = "") do={
:set HostName [ $CharacterReplace [ / ip dhcp-server lease get $Lease mac-address ] ":" "-" ];
}
:if ([ :len $HostName ] > 0) do={
:set Fqdn ($HostName . "." . $Zone);
:set DnsNode [ / ip dns static find where name=$Fqdn ];
:if ([ :len $DnsNode ] > 0) do={
:set DnsIp [ / ip dns static get $DnsNode address ];
:local Leases [ / ip dhcp-server lease find where host-name=$HostName dynamic=yes ];
:local HostNameCount [ / ip dhcp-server lease print count-only where host-name=$HostName dynamic=yes ];
:if ($HostNameCount > 1) do={
:foreach J,Lease in=$Leases do={
:if ($J + 1 = $HostNameCount) do={
:set DhcpIp [ / ip dhcp-server lease get $Lease address ];
}
}
}
:if ($DnsIp = $DhcpIp) do={
:log debug ("DNS entry for " . $Fqdn . " does not need updating.");
} else={
:log info ("Replacing DNS entry for " . $Fqdn . ", new address is " . $DhcpIp . ".");
/ ip dns static set name=$Fqdn address=$DhcpIp ttl=$Ttl comment=$Comment $DnsNode;
}
} else={
:log info ("Adding new DNS entry for " . $Fqdn . ", address is " . $DhcpIp . ".");
/ ip dns static add name=$Fqdn address=$DhcpIp ttl=$Ttl comment=$Comment;
}
}
}