Azure App Service connecting to Azure Sql Database - sql

I have a Web App (Azure App Service) and I have an Azure SQL Database that this Web App talks to. I have two questions regarding communication between the two.
When connecting from the Web App to the Database (using the connection string), does the communication go out to the internet and then back into Azure or does Azure know to keep the traffic locally in Azure?
I have been looking into V-Net Service Endpoints as a possible way to improve speed of communication between the two. It is said that when connecting from a VM on V-Net with Service Endpoints enabled to a SQL Database, that Azure knows to keep the traffic internal to the Azure network and not go out to the internet, is this the same for Azure App Services?
Is it possible to keep traffic between an App Service and SQL Database internal to Azure? If so, how do I go about doing this? Any guidance on this is greatly appreciated.

It knows to keep it local on the "Azure backbone" (as per Azure doco). It doesn't go out to the public internet
Yes
Yes. It is already internal to the "Azure Backbone"
Having said that.... networks are really complicated.
As I understand it the main benefit of V-Net is that you can define your own network and add things to it like firewalls, security groups, subnets, peering between networks. Also it helps when setting up a hybrid network - i.e. connecting Azure resources to an on-premises network. When you can set up the same kind of structures as on premise, it's easier to 'transparently' make it part of the on-premises network. Lastly (rereading the doco), you can remove any incoming public IP firewall rules. These are "Azure backbone" IP addresses but they are also "public internet" addresses
There may be a performance improvement if the App Service and Azure SQL are on the same V-Net.
Azure SQL service endpoints are a bit mysterious. They "connect" to the VNET but you still need to connect to a public address. They don't actually take a up a local IP adress.
Depending on what you are really doing, you might want to look into private endpoint, which actually assigns a private IP to your Azure SQL.

Yes, communication between Azure App Service and Azure SQL Database is "local" within the Azure Virtual Network and does not go out to the public internet.

Related

Deploying Azure application internally

Can anyone suggest some solution for this scenario?:
I have two resources deployed in a VNet: Application Gateway and a VM behind application gateway. (Application gateways in subnet1 and VM in subnet2) There's is no public ip associated with Application Gateway (internal app gateway with only private ip). I have automation scripts in storage account in another tenant and I need to be able to download those inside vm using azure cli. With the given architecture, I want to be able to download the scripts in the vm from storage account. Currently, if I run "az login" from VM, nothing happens. I found some help on Azure documentation :https://learn.microsoft.com/en-us/azure/application-gateway/configuration-overview#allow-application-gateway-access-to-a-few-source-ips but it's not helpful.
I have also attached network security group with allows VnetInbound for VM. In while architecture, I cannot use any public ip because of customer requirements and they do not want any connectivity to internet.
Any suggestions?
Thanks in advance!
Since Azure VM does not attach a public IP, the storage account does not directly communicate with your Azure VM over the Internet.
In this scenario, I would like to provide two suggestions:
The one is to use virtual network service endpoints, which allow you to secure Azure Storage accounts to your virtual networks, fully removing public internet access to these resources. You could create service endpoints for Microsoft.Storage in that VM subnet. You VM instance will access the storage account over the Azure backbone network but it has some limitations as below:
The virtual network where the endpoint is configured can be in the
same or different subscription than the Azure service resource. For
more information on permissions required for setting up endpoints and
securing Azure services, see Provisioning.
Virtual networks and Azure service resources can be in the same or
different subscriptions. If the virtual network and Azure service
resources are in different subscriptions, the resources must be under
the same Active Directory (AD) tenant.
Another suggestion is to use private endpoints for Azure Storage. You could create Private endpoint connections for the storage account in a VNet, then peer this VNet with the VNet where your Azure VM create.
For more references, you could get more details and steps on these blogs--https://stefanstranger.github.io/2019/11/03/UsingAzurePrivateLinkForStorageAccounts/
and
https://kvaes.wordpress.com/2019/03/10/hardening-your-azure-storage-account-by-using-service-endpoints/

Connectivity between Azure SQL MI and On-prme SQL

Scenario :: we want to enable communication between on-premise SQL Server and Azure SQL MI which should be super secure and fast.
After researching a lot, we have found two solutions::
Public endpoint
Site to Site (VPN)
Question :: now we are confused about which way we should go-ahead and Why?
Requirement :: have connectivity between on-prem SQL server and Azure MI so that we can push data to Azure SQL MI via a custom-built application.
The VPN option is difficult to configure if you are not a network expert. You need to have good knowledge of VNet, ExpressRoute and VPN P2S and understand new notions of Azure networking. The VPN option does not provide separation of duties. The VPN option has also some known issues in terms of throughput so the endpoint gives you better performance.
The public endpoint option is easier to configure and allows for separation of duties. Your database administrator will enable the endpoint and the network administrator will make accesible the endpoint by opening port 3342 and provide a UDR route. Your DBA will need RBAC permissions on scope Microsoft.Sql/managedInstances/* while your administrator will need permissions on Microsoft.Network/*.

Accessing Azure SQL from VNET via service endpoint

We have a SQL Azure database and enabled VNET service endpoint. The service endpoint is listed in our VNET and the Azure SQL lists our VNET. According to documentation found here, connections applications inside our VNET should use the Azure backbone and not travel through the public internet.
There was another stack overflow article asking a similar question but I still didn't see an answer (maybe I missed it). That article is here
This is great, but I don't see how to build the connection string to utilize this internal network path since the only name available is the public DNS name (which we can still use with SSMS to manage the server from our on-premise location).
Is Azure smart enough to know that this public DNS name is routed differently when used inside the VNET versus when its used from our on-premise site?
Is Azure smart enough to know that this public DNS name is routed differently when used inside the VNET versus when its used from our on-premise site?
Yes. And that doesn't even require a VNET service endpoint. Connections within Azure, even across Regions never leave Microsoft private networks.
A Virtual Network Service Endpoint is mostly just a firewall rule on your SQL Instance, so you can cut off all public IP access if you want.

Microsoft Azure VPN WebApp not communicating with external SQL

The problem I have is that we're trying to use our WebApp in Microsoft Azure to connect to an external SQL-database (not our own) through a VPN. The SQL-database is only allowing connections from our local IP-addresses that we put up as a Network (for example 176.0.0.0/24).
We are now connected to the same virtual private network, and through our Azure-VM we can now connect to the SQL-Server through SQL Server Management Studio.
Now we want to do the same with a WebApp, but we're not getting through to the server. It gets "Not authenticated" before reaching the SQL-Server (probably the server isn't accepting our IP from the WebApp).
The different problems I have tried to look through is:
Do we only try to connect through our Outbound IPs?
Is the WebApp not connected to the VPN?
I have unfortunatley not found any real answers, and neither any solutions to my problem. If you have any ideas of how to solve our problem, or maybe know how I could tunnel all of the SQL-calls through the VM, the help would be very much appreciated!
Hybrid connection is one option. What you can also do is enable point-to-site in your VPN. Once you do that, you can directly integrate your web app to the vnet and your connections will work. (Go to your web app -> Settings -> Networking -> VNet Integration)
If your Vnet is V1(older way of creating VNs) then enabling point to site is very straightforward. You can do it through portal. For V2 Vnets you have to do it through powershell commands.
Here is a link for the documentation which explains both the options.
https://azure.microsoft.com/en-in/documentation/articles/web-sites-integrate-with-vnet/
There's a way to "tunnel all of the SQL-calls through the VM". You may want to use hybrid connections (cf https://azure.microsoft.com/en-us/documentation/articles/integration-hybrid-connection-overview/).
The principle is to have an agent installed on the VM that can access the database with the correct IP address.
Suppose you can access the SQL DB as mysqldbsrv from the VM. You add an hybrid connection associated to your web app, you install the agent on the VM. Then, when you connect to mysqldbsrv from the Web App, you go through the VM.

Connect windows application to SQL Server througn VPN

We have developed a cloud based POS system which running on more that 75 outlets and all the transaction data need to be posted every 5 minutes to the relevant database which sits on our head office (POS System is connecting to its own local database). For this we are using windows application which is directly connecting to our head office database through a VPN. But recently one of our clients raised a concern that our head office database is exposed because if anyone sneak to the network (obviously inside the VPN) he could see all CRUD Operations. So by this way he could do anything to head office database.
So we have decided to go for a WCF solution with encrypted JSON Call. If we use a web service can we eliminate this issueccompletely. Is it the best practice? Please advice.
There are several aspects of security to consider in your situation. If your current network topology doesn't limit the VPN client's visibility to just your database server, then yes, I agree that moving to publishing a web service endpoint and using HTTPS would improve security by blocking clients access to other servers on your internal network. However, the web service solution introduces some other considerations. Will you use firewall rules to limit which clients can access the web service? How are you authenticating clients, and how are you protecting those credentials from unauthorized users?