diff --git a/cacert.com b/cacert.com
index 2dfa4b8..cbd3f8e 100644
--- a/cacert.com
+++ b/cacert.com
@@ -1,10 +1,10 @@
 ; DNS master zone file for cacert.com, under RCS control
-; @(#)(CAcert) $Id: cacert.com,v 1.24 2018/05/02 12:48:09 root Exp $
+; @(#)(CAcert) $Id: cacert.com,v 1.25 2019/06/06 08:41:38 root Exp $
 
 $TTL	12h	;	default TTL for zone data
 
 @	1h	IN	SOA	ns1.cacert.com. hostmaster.cacert.com. (
-					2018050201	; Serial
+					2019060601	; Serial
 					4h		; refresh time
 					1h		; retry interval
 					7d		; expire time
@@ -12,7 +12,6 @@ $TTL	12h	;	default TTL for zone data
 
 @		IN	NS	ns1.cacert.com.
 @		IN	NS	ns3.cacert.com.
-@		IN	NS	ns4.cacert.com.
 @		IN	NS	ns5.cacert.com.
 
 @		IN	A	213.154.225.245
@@ -25,9 +24,7 @@ $TTL	12h	;	default TTL for zone data
 ns1		IN	A	213.154.225.251		; ns.cacert.org
 ns1		IN	AAAA	2001:7b8:616:0163::102
 ns3		IN	A	46.249.47.169		; mars.overmeer.net
-;; ns3		IN	AAAA	2a00:1ca8:2a::31
-ns4		IN	A	185.49.140.62		; ns-ext.nlnetlabs.nl
-ns4		IN	AAAA	2a04:b900::8:0:0:62
+ns3		IN	AAAA	2a00:1ca8:2a::31
 ns5		IN	A	192.5.4.1		; sns-pb.isc.org
 ns5		IN	AAAA	2001:500:2e::1
 www		IN	CNAME	cacert.com.
diff --git a/cacert.com.log b/cacert.com.log
index 58c1652..5a824df 100644
--- a/cacert.com.log
+++ b/cacert.com.log
@@ -1,16 +1,21 @@
 
 RCS file: /var/opendnssec/unsigned/RCS/cacert.com,v
 Working file: /var/opendnssec/unsigned/cacert.com
-head: 1.24
+head: 1.25
 branch:
 locks: strict
 access list:
 symbolic names:
 keyword substitution: kv
-total revisions: 24;	selected revisions: 24
+total revisions: 25;	selected revisions: 25
 description:
 cacert.com - zone file for cacert.com
 ----------------------------
+revision 1.25
+date: 2019/06/06 08:41:38;  author: root;  state: Exp;  lines: +3 -6
+Drop ns4.cacert.org secondary server.
+Re-enable IPv6 address for ns3.cacert.com.
+----------------------------
 revision 1.24
 date: 2018/05/02 12:48:09;  author: root;  state: Exp;  lines: +3 -3
 Update CAA record to contain a valid mailto: URL.
diff --git a/cacert.net b/cacert.net
index c13227a..900238f 100644
--- a/cacert.net
+++ b/cacert.net
@@ -1,10 +1,10 @@
 ; DNS master zone file for cacert.net, under RCS control
-; @(#)(CAcert) $Id: cacert.net,v 1.25 2018/05/02 12:48:09 root Exp $
+; @(#)(CAcert) $Id: cacert.net,v 1.26 2019/06/06 08:41:38 root Exp $
 
 $TTL	12h	;	default TTL for zone data
 
 @	1h	IN	SOA	ns1.cacert.net. hostmaster.cacert.net. (
-					2018050201	; Serial
+					2019060601	; Serial
 					4h		; refresh time
 					1h		; retry interval
 					7d		; expire time
@@ -12,7 +12,6 @@ $TTL	12h	;	default TTL for zone data
 
 @		IN	NS	ns1.cacert.net.
 @		IN	NS	ns3.cacert.net.
-@		IN	NS	ns4.cacert.net.
 @		IN	NS	ns5.cacert.net.
 
 @		IN	A	213.154.225.245
@@ -25,9 +24,7 @@ $TTL	12h	;	default TTL for zone data
 ns1		IN	A	213.154.225.251		; ns.cacert.org
 ns1		IN	AAAA	2001:7b8:616:0163::102
 ns3		IN	A	46.249.47.169		; mars.overmeer.net
-;; ns3		IN	AAAA	2a00:1ca8:2a::31
-ns4		IN	A	185.49.140.62		; ns-ext.nlnetlabs.nl
-ns4		IN	AAAA	2a04:b900::8:0:0:62
+ns3		IN	AAAA	2a00:1ca8:2a::31
 ns5		IN	A	192.5.4.1		; sns-pb.isc.org
 ns5		IN	AAAA	2001:500:2e::1
 www		IN	CNAME	cacert.net.
diff --git a/cacert.net.log b/cacert.net.log
index 98f4e14..c358e54 100644
--- a/cacert.net.log
+++ b/cacert.net.log
@@ -1,16 +1,21 @@
 
 RCS file: /var/opendnssec/unsigned/RCS/cacert.net,v
 Working file: /var/opendnssec/unsigned/cacert.net
-head: 1.25
+head: 1.26
 branch:
 locks: strict
 access list:
 symbolic names:
 keyword substitution: kv
-total revisions: 25;	selected revisions: 25
+total revisions: 26;	selected revisions: 26
 description:
 cacert.net - DNS master zone file for cacert.net, under RCS control
 ----------------------------
+revision 1.26
+date: 2019/06/06 08:41:38;  author: root;  state: Exp;  lines: +3 -6
+Drop ns4.cacert.org secondary server.
+Re-enable IPv6 address for ns3.cacert.net.
+----------------------------
 revision 1.25
 date: 2018/05/02 12:48:09;  author: root;  state: Exp;  lines: +3 -3
 Update CAA record to contain a valid mailto: URL.