diff --git a/cloud-init-templates/boothook_centos.jinja2 b/cloud-init-templates/boothook_centos.jinja2
index b8dbe8f..732bf75 100644
--- a/cloud-init-templates/boothook_centos.jinja2
+++ b/cloud-init-templates/boothook_centos.jinja2
@@ -48,12 +48,14 @@ fi
 
 cloud-init-per instance conntrack_ipv4 /bin/sh -c 'echo nf_conntrack_ipv4 | tee -a /etc/rc.modules'
 cloud-init-per instance conntrack_ipv6 /bin/sh -c 'echo nf_conntrack_ipv6 | tee -a /etc/rc.modules'
+cloud-init-per instance conntrack_proto_gre /bin/sh -c 'echo nf_conntrack_proto_gre | tee -a /etc/rc.modules'
 cloud-init-per instance chmod_rc_modules chmod +x /etc/rc.modules
 cloud-init-per instance conntrack_max /bin/sh -c 'echo "net.nf_conntrack_max=1048576" | tee -a /etc/sysctl.conf'
 cloud-init-per instance kernel_panic /bin/sh -c 'echo "kernel.panic=60" | tee -a /etc/sysctl.conf'
 
 cloud-init-per instance conntrack_ipv4_load modprobe nf_conntrack_ipv4
 cloud-init-per instance conntrack_ipv6_load modprobe nf_conntrack_ipv6
+cloud-init-per instance conntrack_proto_gre_load modprobe nf_conntrack_proto_gre
 cloud-init-per instance conntrack_max_set sysctl -w "net.nf_conntrack_max=1048576"
 cloud-init-per instance kernel_panic_set sysctl -w "kernel.panic=60"
 
diff --git a/cloud-init-templates/boothook_ubuntu.jinja2 b/cloud-init-templates/boothook_ubuntu.jinja2
index 60bf636..e3c7dd9 100644
--- a/cloud-init-templates/boothook_ubuntu.jinja2
+++ b/cloud-init-templates/boothook_ubuntu.jinja2
@@ -55,11 +55,13 @@ fi
 
 cloud-init-per instance conntrack_ipv4 /bin/sh -c 'echo nf_conntrack_ipv4 | tee -a /etc/modules'
 cloud-init-per instance conntrack_ipv6 /bin/sh -c 'echo nf_conntrack_ipv6 | tee -a /etc/modules'
+cloud-init-per instance conntrack_proto_gre /bin/sh -c 'echo nf_conntrack_proto_gre | tee -a /etc/modules'
 cloud-init-per instance conntrack_max /bin/sh -c 'echo "net.nf_conntrack_max=1048576" | tee -a /etc/sysctl.conf'
 cloud-init-per instance kernel_panic /bin/sh -c 'echo "kernel.panic=60" | tee -a /etc/sysctl.conf'
 
 cloud-init-per instance conntrack_ipv4_load modprobe nf_conntrack_ipv4
 cloud-init-per instance conntrack_ipv6_load modprobe nf_conntrack_ipv6
+cloud-init-per instance conntrack_proto_gre_load modprobe nf_conntrack_proto_gre
 cloud-init-per instance conntrack_max_set sysctl -w "net.nf_conntrack_max=1048576"
 cloud-init-per instance kernel_panic_set sysctl -w "kernel.panic=60"