Disable TCP early demux when pod-eni is enabled

Author: SaranBalaji90

scripts/init.sh

@@ -28,6 +28,12 @@ HOST_IP=$(curl -H "X-aws-ec2-metadata-token: $TOKEN" http://169.254.169.254/late
 PRIMARY_IF=$(ip -4 -o a | grep "$HOST_IP" | awk '{print $2}')
 sysctl -w "net.ipv4.conf.$PRIMARY_IF.rp_filter=2"
 
+# Configure tcp_early_demux to enable kubelet to pod-eni communication
+# https://lwn.net/Articles/503420/ for background
+if ! [[ -z "$ENABLE_POD_ENI" ]]; then
+    sysctl -w "net.ipv4.tcp_early_demux=0"
+fi
+
 cat "/proc/sys/net/ipv4/conf/$PRIMARY_IF/rp_filter"
 
 echo "CNI init container done"