Overview Of Azure On-Premise Data Gateway

Introduction

If you are a novice to Azure cloud and want to learn what a logic app is, then go through my previous articles.

In this article, we will explore the overview of one of the services, named On-premise Data Gateway, in Azure.

Scenario

This article will help you to understand what an on-premise data gateway is, and in the next articles, we will go through the steps to help you how to install and configure it with a step-by-step approach. Let’s gear up.

Prerequisites

Basic knowledge of Azure Services

Background

When you migrate/redesign/develop your application to the cloud, then many times, you need to connect to the resources that are present in on-premise servers.
On-premise data gateway works with the following Azure resources.
- Logic Apps
- Power BI
- Microsoft Flow
- Azure Analysis Services

Overview

The on-premise data gateway service comes under the integration services category in Azure.
This gateway is nothing but a bridge between on-premise resources and Azure resources.
If we need to connect with on-premise resources; e.g., SQL or FTP data source, etc., from Azure Services like Logic Apps, Power BI, Microsoft Flow, and Azure Analysis Services, then on-premise data gateway is one of the efficient and accurate solutions to make this integration possible.
It helps us to communicate between two environments securely by encrypting the data and credentials without modifying the firewall settings.
This gateway supports only Logic Apps, Power BI, Microsoft Flow, and Azure Analysis Services.
- Power BI: Power BI list of on-premise data source types
- Flow: List
- Logic Apps: List
Transmission of data between these two environments happens through data compression and transport encryption.

How it works?

Send a request from Azure resources to the Azure service bus through the connector.
Connector builds a query with credentials and sends it to Azure Service Bus (fully managed enterprise integration message broker service).
Azure service bus keeps requests in the queue for processing.
On-premise data gateway polls and receives the pending requests from Azure service bus.

Note

The gateway creates an outbound connection to the Azure Service Bus. It communicates on outbound ports: TCP 443 (default), 5671, 5672, 9350 through 9354. We can also able to force to use HTTPs but that leads to reducing the performance.

The gateway decrypts the credentials and connects to the data sources with those credentials and sends a request to execute it.
On-premise data source executes the query and the results are sent back to the gateway
Finally, the on-premise data gateway sends the results to the cloud service.
The below image by Microsoft shows the detailed data flow of the on-premise data gateway

What about troubleshooting?

On-premise data gateway maintains logs to help developers
Gateway service logs: C:\Users\PBIEgwService\AppData\Local\Microsoft\On-premises data gateway\<yyyyymmdd>.<Number>.log
Configuration logs: C:\Users\<username>\AppData\Local\Microsoft\On-premises data gateway\GatewayConfigurator.log
Event logs: We can get it under Application and Services Logs.
- Open the event viewer.
- Expand ‘event viewer (local)’
- Go to ‘applications and services logs’
- Select ‘on-premises data gateway service’

Availability and Disaster Recovery

For communication to Azure service from the on-premise data gateway, the gateway should be in a running state.
When we install the gateway in the on-premise machine then we need to use one key called recovery key.
By using the recovery key, we can restore or move the gateway to other machines.
The recovery key also helps to migrate or recover the earlier settings of the gateway.

Note

A single gateway can connect to multiple data sources.
It is not compulsory to install this on-premise gateway connector on the machine where the data source is present.
To minimize latency, you can install the gateway as close as possible to your data source, or on the same computer, assuming that you have permissions.
We can install it anywhere within your on-premise network, but the destination data source must be accessible from a machine where the gateway is installed.
Azure Application gateway and on-premise gateway are different things. Don’t be confused.

Summary

In this part 1, we have learned an overview of the on-premise gateway and its features.

In the next article, we will learn to execute the steps to install and configure it on on-premise machine.