diff --git a/security/acme-client/pkg-descr b/security/acme-client/pkg-descr
index 670324157..ee87936d9 100644
--- a/security/acme-client/pkg-descr
+++ b/security/acme-client/pkg-descr
@@ -12,6 +12,7 @@ Plugin Changelog
 
 Added:
 * new automation: update local Unifi keystore (#2664)
+* add support for dynv6 HTTP API (#2678)
 
 Fixed:
 * fix SFTP upload (#2671)
diff --git a/security/acme-client/src/opnsense/mvc/app/controllers/OPNsense/AcmeClient/forms/dialogValidation.xml b/security/acme-client/src/opnsense/mvc/app/controllers/OPNsense/AcmeClient/forms/dialogValidation.xml
index 36a285356..2f13068c8 100644
--- a/security/acme-client/src/opnsense/mvc/app/controllers/OPNsense/AcmeClient/forms/dialogValidation.xml
+++ b/security/acme-client/src/opnsense/mvc/app/controllers/OPNsense/AcmeClient/forms/dialogValidation.xml
@@ -1353,4 +1353,14 @@
         <label>Secret API Key</label>
         <type>password</type>
     </field>
+    <field>
+        <label>dynv6 HTTP API</label>
+        <type>header</type>
+        <style>table_dns table_dns_dynv6</style>
+    </field>
+    <field>
+        <id>validation.dns_dynv6_token</id>
+        <label>HTTP Token</label>
+        <type>password</type>
+    </field>
 </form>
diff --git a/security/acme-client/src/opnsense/mvc/app/library/OPNsense/AcmeClient/LeValidation/DnsDynv6.php b/security/acme-client/src/opnsense/mvc/app/library/OPNsense/AcmeClient/LeValidation/DnsDynv6.php
new file mode 100644
index 000000000..c1d9115f0
--- /dev/null
+++ b/security/acme-client/src/opnsense/mvc/app/library/OPNsense/AcmeClient/LeValidation/DnsDynv6.php
@@ -0,0 +1,44 @@
+<?php
+
+/*
+ * Copyright (C) 2021 Frank Wall
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
+ * OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+namespace OPNsense\AcmeClient\LeValidation;
+
+use OPNsense\AcmeClient\LeValidationInterface;
+use OPNsense\Core\Config;
+
+/**
+ * dynv6 HTTP API
+ * @package OPNsense\AcmeClient
+ */
+class DnsDynv6 extends Base implements LeValidationInterface
+{
+    public function prepare()
+    {
+        $this->acme_env['DYNV6_TOKEN'] = (string)$this->config->dns_dynv6_token;
+    }
+}
diff --git a/security/acme-client/src/opnsense/mvc/app/models/OPNsense/AcmeClient/AcmeClient.xml b/security/acme-client/src/opnsense/mvc/app/models/OPNsense/AcmeClient/AcmeClient.xml
index 0fa09b84c..982ffaf3b 100644
--- a/security/acme-client/src/opnsense/mvc/app/models/OPNsense/AcmeClient/AcmeClient.xml
+++ b/security/acme-client/src/opnsense/mvc/app/models/OPNsense/AcmeClient/AcmeClient.xml
@@ -417,6 +417,7 @@
                         <dns_duckdns>DuckDNS API</dns_duckdns>
                         <dns_dyn>Dyn Managed DNS API</dns_dyn>
                         <dns_dynu>Dynu API</dns_dynu>
+                        <dns_dynv6>dynv6 HTTP API</dns_dynv6>
                         <dns_euserv>EUserv</dns_euserv>
                         <dns_freedns>FreeDNS API</dns_freedns>
                         <dns_gandi_livedns>Gandi LiveDNS API</dns_gandi_livedns>
@@ -1018,6 +1019,9 @@
                 <dns_zone_key type="TextField">
                     <Required>N</Required>
                 </dns_zone_key>
+                <dns_dynv6_token type="TextField">
+                    <Required>N</Required>
+                </dns_dynv6_token>
             </validation>
         </validations>
         <actions>