A common problem on Linux systems is running out of space in the conntrack table, which can cause poor iptables performance. This can happen if you run a lot of workloads on a given host, or if your workloads create a lot of TCP connections or bidirectional UDP streams.
To avoid this becoming a problem, we recommend increasing the conntrack table size. To do so, run the following commands:
sysctl -w net.netfilter.nf_conntrack_max=1000000 echo "net.netfilter.nf_conntrack_max=1000000" >> /etc/sysctl.conf