Added workbook sample for Azure Firewall.

deploy/src/core-net-firewall/workbook/README.md

@@ -0,0 +1,31 @@
+# Azure Firewall Workbook
+
+This is an earlier sample workbook for analyzing Azure Firewall Diagnostics. It
+differs from the new workbook and is focused towards troubleshooting packet
+flows to determine accuracy of rules.
+
+# Get started
+
+## Prerequisites
+
+Follow the pre-requisite guidance in the following article:
+
+- [Monitor logs using Azure Firewall
+  Workbook](https://docs.microsoft.com/en-us/azure/firewall/firewall-workbook)
+
+## Install
+
+Create a new Workbook in Azure Monitor and use the Advanced Edditing option to
+replace the workbook json with the provided sample.
+
+![azure-monitor-workbook-advanced-edit](../../../../png/azure-monitor-workbook-advanced-edit.png)
+
+# Resources
+
+Additional information about monitoring Azure Firewall is available in the
+following articles:
+
+- [Monitor Azure Firewall logs and metrics | Microsoft
+  Docs](https://docs.microsoft.com/en-us/azure/firewall/firewall-diagnostics)
+- [Azure Monitor Workbooks Overview - Azure Monitor | Microsoft
+  Docs](https://docs.microsoft.com/en-us/azure/azure-monitor/platform/workbooks-overview)