Overview

High Iptables rules count in Azure firewall could lead to performance issues. It is advised to keep the lines in iptables for Azure Firewall below 20K.

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• 20,000 unique source/destinations in network rules
• Unique source/destinations in network = sum of (unique source addresses * unique destination addresses for each rule)
• An IP group counts as one address, regardless of how many IP addresses it contains.
• You can track the Firewall Policy network rule count in the policy analytics under the Insights tab. As a proxy, you can also monitor your Firewall Latency Probe metrics to ensure it stays within 20 ms even during peak hours.
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