-net.ipv4.ip_conntrack_tcp_timeouts="300 43200 120 60 120 120 10 60 30 120"
-net.ipv4.ip_conntrack_udp_timeouts="60 180"
+
+net.ipv4.netfilter.ip_conntrack_checksum=0
+net.ipv4.netfilter.ip_conntrack_max=16384
+net.ipv4.netfilter.ip_conntrack_tcp_timeout_established=3600
+net.ipv4.netfilter.ip_conntrack_udp_timeout=60
+net.ipv4.netfilter.ip_conntrack_udp_timeout_stream=180
+net.ipv6.conf.all.forwarding=1
+
+net.netfilter.nf_conntrack_acct=1
+net.netfilter.nf_conntrack_checksum=0
+net.netfilter.nf_conntrack_max=16384
+net.netfilter.nf_conntrack_tcp_timeout_established=3600
+net.netfilter.nf_conntrack_udp_timeout=60
+net.netfilter.nf_conntrack_udp_timeout_stream=180
+
+# disable bridge firewalling by default
+net.bridge.bridge-nf-call-arptables=0
+net.bridge.bridge-nf-call-ip6tables=0
+net.bridge.bridge-nf-call-iptables=0