From bb4682eceea9a0d6d8e1420c5ad61e12a857de0c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=D0=98=D0=B3=D0=BE=D1=80=D1=8C=20=D0=91=D0=B0=D1=80=D0=BA?=
 =?UTF-8?q?=D0=BE=D0=B2?= <ibarkov@likom.com.ua>
Date: Thu, 8 Aug 2024 13:22:01 +0000
Subject: [PATCH] =?UTF-8?q?=D0=94=D0=BE=D0=B1=D0=B0=D0=B2=D0=B8=D1=82?=
 =?UTF-8?q?=D1=8C=20DHCP2DNS=5FCLEANUP?=
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---
 DHCP2DNS_CLEANUP | 40 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)
 create mode 100644 DHCP2DNS_CLEANUP

diff --git a/DHCP2DNS_CLEANUP b/DHCP2DNS_CLEANUP
new file mode 100644
index 0000000..388c81e
--- /dev/null
+++ b/DHCP2DNS_CLEANUP
@@ -0,0 +1,40 @@
+# Remove static DNS entries that are no longer in the DHCP lease list
+:foreach dnsRecord in=[/ip dns static find where comment~"#DHCP"] do={
+
+    :local dnsName [/ip dns static get $dnsRecord name]
+    :local dnsTTL [/ip dns static get $dnsRecord ttl]
+    :local dnsAddress [/ip dns static get $dnsRecord address]
+    
+    :local found false
+
+    # Check if the DNS name exists in the DHCP lease list
+    :foreach lease in=[/ip dhcp-server lease find] do={
+        :local hostName [/ip dhcp-server lease get $lease host-name]
+        :local ipAddress [/ip dhcp-server lease get $lease address]
+        :local ttl [/ip dhcp-server lease get $lease expires-after]
+        
+        # Find the corresponding network for the lease's IP address
+        :local networkId [/ip dhcp-server network find where $ipAddress in address]
+        :local domainName [/ip dhcp-server network get $networkId domain]
+
+        :local fqdn "$hostName.$domainName"
+
+        :if ($fqdn = $dnsName) do={
+            :set found true
+            
+            # Update TTL if it's different
+            :if ($dnsTTL != $ttl) do={
+                :log info "Updating TTL for $dnsName from $dnsTTL to $ttl"
+                /ip dns static set $dnsRecord ttl=$ttl
+            }
+
+            :break
+        }
+    }
+
+    # If not found, remove the DNS static entry
+    :if (!$found) do={
+        :log info "Removing static DNS entry: $dnsName"
+        /ip dns static remove $dnsRecord
+    }
+}
\ No newline at end of file