diff --git a/config/etc/sysctl.conf b/config/etc/sysctl.conf
index b2934577e..df3ef5f96 100644
--- a/config/etc/sysctl.conf
+++ b/config/etc/sysctl.conf
@@ -24,3 +24,7 @@ kernel.printk = 1 4 1 7
 vm.swappiness=0
 vm.mmap_min_addr = 4096
 vm.min_free_kbytes = 8192
+
+# Disable IPv6 by default.
+net.ipv6.conf.all.disable_ipv6 = 1
+net.ipv6.conf.default.disable_ipv6 = 1
diff --git a/config/kernel/kernel.config.armv5tel-ipfire-kirkwood b/config/kernel/kernel.config.armv5tel-ipfire-kirkwood
index ead83d58e..be66adf72 100644
--- a/config/kernel/kernel.config.armv5tel-ipfire-kirkwood
+++ b/config/kernel/kernel.config.armv5tel-ipfire-kirkwood
@@ -503,7 +503,7 @@ CONFIG_TCP_CONG_ILLINOIS=m
 CONFIG_DEFAULT_RENO=y
 CONFIG_DEFAULT_TCP_CONG="reno"
 # CONFIG_TCP_MD5SIG is not set
-CONFIG_IPV6=m
+CONFIG_IPV6=y
 # CONFIG_IPV6_PRIVACY is not set
 # CONFIG_IPV6_ROUTER_PREF is not set
 # CONFIG_IPV6_OPTIMISTIC_DAD is not set
diff --git a/config/kernel/kernel.config.armv5tel-ipfire-omap b/config/kernel/kernel.config.armv5tel-ipfire-omap
index 8765ae5b5..8e0d2d653 100644
--- a/config/kernel/kernel.config.armv5tel-ipfire-omap
+++ b/config/kernel/kernel.config.armv5tel-ipfire-omap
@@ -595,7 +595,7 @@ CONFIG_TCP_CONG_ILLINOIS=m
 CONFIG_DEFAULT_RENO=y
 CONFIG_DEFAULT_TCP_CONG="reno"
 # CONFIG_TCP_MD5SIG is not set
-CONFIG_IPV6=m
+CONFIG_IPV6=y
 # CONFIG_IPV6_PRIVACY is not set
 # CONFIG_IPV6_ROUTER_PREF is not set
 # CONFIG_IPV6_OPTIMISTIC_DAD is not set
diff --git a/config/kernel/kernel.config.armv5tel-ipfire-rpi b/config/kernel/kernel.config.armv5tel-ipfire-rpi
index 2cef33def..584588514 100644
--- a/config/kernel/kernel.config.armv5tel-ipfire-rpi
+++ b/config/kernel/kernel.config.armv5tel-ipfire-rpi
@@ -493,7 +493,7 @@ CONFIG_TCP_CONG_ILLINOIS=m
 CONFIG_DEFAULT_RENO=y
 CONFIG_DEFAULT_TCP_CONG="reno"
 # CONFIG_TCP_MD5SIG is not set
-CONFIG_IPV6=m
+CONFIG_IPV6=y
 # CONFIG_IPV6_PRIVACY is not set
 # CONFIG_IPV6_ROUTER_PREF is not set
 # CONFIG_IPV6_OPTIMISTIC_DAD is not set
diff --git a/config/kernel/kernel.config.i586-ipfire b/config/kernel/kernel.config.i586-ipfire
index d2ad82751..1fbffadfe 100644
--- a/config/kernel/kernel.config.i586-ipfire
+++ b/config/kernel/kernel.config.i586-ipfire
@@ -658,7 +658,7 @@ CONFIG_TCP_CONG_ILLINOIS=m
 CONFIG_DEFAULT_RENO=y
 CONFIG_DEFAULT_TCP_CONG="reno"
 # CONFIG_TCP_MD5SIG is not set
-CONFIG_IPV6=m
+CONFIG_IPV6=y
 # CONFIG_IPV6_PRIVACY is not set
 # CONFIG_IPV6_ROUTER_PREF is not set
 # CONFIG_IPV6_OPTIMISTIC_DAD is not set
diff --git a/config/kernel/kernel.config.i586-ipfire-pae b/config/kernel/kernel.config.i586-ipfire-pae
index 9dd0d3936..a2fe11df0 100644
--- a/config/kernel/kernel.config.i586-ipfire-pae
+++ b/config/kernel/kernel.config.i586-ipfire-pae
@@ -681,7 +681,7 @@ CONFIG_TCP_CONG_ILLINOIS=m
 CONFIG_DEFAULT_RENO=y
 CONFIG_DEFAULT_TCP_CONG="reno"
 # CONFIG_TCP_MD5SIG is not set
-CONFIG_IPV6=m
+CONFIG_IPV6=y
 # CONFIG_IPV6_PRIVACY is not set
 # CONFIG_IPV6_ROUTER_PREF is not set
 # CONFIG_IPV6_OPTIMISTIC_DAD is not set
diff --git a/config/kernel/kernel.config.i586-ipfire-xen b/config/kernel/kernel.config.i586-ipfire-xen
index 7ba0b87db..2d9a945be 100644
--- a/config/kernel/kernel.config.i586-ipfire-xen
+++ b/config/kernel/kernel.config.i586-ipfire-xen
@@ -471,7 +471,7 @@ CONFIG_TCP_CONG_ILLINOIS=m
 CONFIG_DEFAULT_RENO=y
 CONFIG_DEFAULT_TCP_CONG="reno"
 # CONFIG_TCP_MD5SIG is not set
-CONFIG_IPV6=m
+CONFIG_IPV6=y
 # CONFIG_IPV6_PRIVACY is not set
 # CONFIG_IPV6_ROUTER_PREF is not set
 # CONFIG_IPV6_OPTIMISTIC_DAD is not set