Is it possible to connect an Azure Web App to a SQL Managed Instance via the private endpoint for the MI?
Following the documentation here https://learn.microsoft.com/en-us/azure/sql-database/sql-database-managed-instance-connect-app it seems to be that as long as the web app service is in the same VNET as the managed instance, then the connection should be OK via the private endpoint.
I have enabled VNET integration on the app service so that it is integrated into the same VNET as the managed instance. I have also whitelisted all of the outbound IP addresses for the webapp (including the additional ones) on port 1433 for the MI.
Using the private connection string for the MI, the webapp fails to connect when loading the front end and also when checking the connection string via the diagnostic tools.
Enabling the public endpoint on the MI and whitelisting all outbound IPs on port 3342, the webapp is able to connect straight away with no issues. Switching back to the private endpoint fails again.
The error message received is:
System.Data.SqlClient.SqlException: A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server)
Came across this issue as well, a simple restart after the vnet-integration activated the connection for me
Related
I am trying to retrieve data from a table located in a postgresql database hosted on azure VM. I would like to inject this data into an Azure SQL Database. I set up the self hosted integration runtime. Since the Vm hosting my DB is a linux VM, i have setup self-hosted IR on windows VM and using that I am able to connect to DB and copy the data to ABS location without any problem but when I try to copy the same data to SQL database, I am getting following error:
ErrorCode=SqlFailedToConnect,'Type=Microsoft.DataTransfer.Common.Shared.HybridDeliveryException,Message=Cannot connect to SQL Database: 'XXX', Database: 'XXX', User: 'XXX'. Check the linked service configuration is correct, and make sure the SQL Database firewall allows the integration runtime to access.,Source=Microsoft.DataTransfer.ClientLibrary,''Type=System.Data.SqlClient.SqlException,Message=A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: TCP Provider, error: 0 - A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond.),
Source=.Net SqlClient Data Provider,SqlErrorNumber=10060,Class=20,ErrorCode=-2146232060,State=0,Errors=[{Class=20,Number=10060,State=0,Message=A network-related or instance-specific error occurred while establishing a connection to SQL Server. ...
After searching about I opened the inbound and outbound traffic for port 1433 on machine which is hosting IR and and outbound traffic for port 1433 on machine which is hosting the database but I am still getting the same error.
Any idea what am I missing here?
I managed to solve the problem. As per azure documentation here, if we are trying to connect to SQL database from within Azure cloud then we need to open communication to port range 11000-11999. We need to put this port range in network security list for outbound connections.
We have created the Vnet with virtual network gateway for point to site VPN, PostgresDB, Azure function APP.
We are able to establish connections with a point-to-site VPN.
Configuration:
Resources configuration in Azure functions:- Private endpoint and
vnet integration.
Resources configuration in PostgresDB:- Private endpoint and in
connection security set Deny public network access to "Yes"
If in PostgresDB we configured Deny public network to "No" then azure function communicating to Postgres DB and works find.
Issue :
when we are trying to access Azure DB from Private function with hostname its failed to establish the connection but it works if we replace Azure DB hostname with private IP.
Same with VPN connection when we try to connect Postgress DB with server name it doesn't work but works with private endpoint IP.
Error:-
Result: Failure Exception: OperationalError: FATAL: The public network access on this server is disabled. To connect to this server, use the Private Endpoint from inside your virtual network.
we need a solution to create a connection between the azure function to private Postgres DB.
In order to solve the above issue, please check the below points.
Enable private endpoint at Azure Function & DB
If you are denying the public network access to 'Yes' then you need to make allow Azure Service to 'Yes' and add Vnet Rule with function subnet.
Go to the private DNS zones and check vnet(Vnet in which DB & Function created) are added into the private DNS zone.
I have SQL Azure Database Server (not managed instance). When setup last year, I added Azure Virtual Network Gateway, and I could access the database via the VPN connection, without whitelisting the IP.
We didn't use this connection via gateway since Jan 2020. There was only couple of developers connection but had their IP whitelisted.
Recently, we tried accessing the database using this connection, and it doesn't work. Prompting to whitelist the IP. Has something changed?
It seems that you just enable Azure virtual network service endpoints for your Azure SQL database server (not managed instance) and add this subnet to your SQL network rules. With service endpoint, the traffics go over the Internet but restrict over the network. Service endpoints and Private endpoints are two different things.
To connect to your Azure SQL database via a VPN connection, you could use a private link. Private Link allows you to connect to various PaaS services in Azure via a private endpoint. You could get the detailed steps from https://learn.microsoft.com/en-us/azure/azure-sql/database/private-endpoint-overview
Alternatively, you could try to use a TCP proxy server to forward traffic to the public IP address for SQL Database. Reference: https://argonsys.com/microsoft-cloud/library/using-a-tcp-proxy-to-connect-to-sql-database-over-vpn/
I've created a SQL Server and then created a private link with my TESTVNET/SUBNET1 with private IP 10.1.1.4. I've now disabled Public access for the SQL server.
I have an Azure function running on App Service which I've VNET Integrated with VNET/SUBNET2.
Subnet 2 shows it's delegated to server farms. (also if someone can explain what does delegate to means, I found I cannot create any VM in that subnet as well, probably it's just can't be useful for any other purpose)
Now when my azure function tries to connect to DB. it fails with below error:
2020-08-30T15:25:45.216 [Error] Unhandled rejection SequelizeAccessDeniedError: Cannot open server "10.1.1.4" requested by the login. The login failed.
However, if I give the public FQDN it gives me below error.
2020-08-30T15:29:43.654 [Error] Unhandled rejection SequelizeAccessDeniedError: Reason: An instance-specific error occurred while establishing a connection to SQL Server. The public network interface on this server is not accessible. To connect to this server, use the Private Endpoint from inside your virtual network.
Here the Private DNS created by Private endpoint should have been ideally used to get the private IP of the SQL database, but it seems the function is not using the private DNS probably because not running in an isolated environment.
Now in my Azure function Application settings, I've added WEBSITE_VNET_ROUTE_ALL =1 which should mean that all the requests should be routed to VNET. So now If I enable public access internet, and allow Azure services to access DB (I think azure added the public IP by default). The function gets connected to the DB.
Now I want to understand where I'm going wrong and why is the private endpoint connection not working. Any help is appreciated.
In the DB firewall settings, I've allowed traffic from below to subnets:
Network Configuration
TESTVNET: 10.1.0.0/16
SUBNET 1: 10.1.1.0/24
SUBNET 2: 10.1.2.0/24
I've disabled Service endpoint for SQL in both SUBNET 1 and SUBNET 2. My NSG has default settings i.e.
AllowVnetInBound, AllowAzureLoadBalancerInBound, DenyAllInBound
AllowVnetOutBound, AllowInternetOutBound, DenyAllOutBound.
Since my private link has a private IP present in the same VNET I don't think NSG should have any impact.
New to Azure, testing things out. Thank you for your patience.
To make Azure Function connect to a private endpoint you will need to use VNET integration.
After your app integrates with your VNet, it uses the same DNS server that your VNet is configured with. By default, your app won't work with Azure DNS Private Zones. To work with Azure DNS Private Zones you need to add the following app settings:
WEBSITE_DNS_SERVER with value 168.63.129.16
WEBSITE_VNET_ROUTE_ALL with value 1
These settings will send all of your outbound calls from your app into your VNet in addition to enabling your app to use Azure DNS private zones. Reference here.
Then you could set up Private Link for Azure SQL Database. You can create an Azure VM from a new subnet in the same VNet to check connectivity using SQL Server Management Studio (SSMS). If you enable the private endpoint, you should get a client private IP from that Azure VM to connect the Azure SQL database with its FQDN.
For more information, you could read private endpoint VS service endpoint in this blog.
I've deployed my version in windows azure.
After that I've added sql database. When I trying to connect, it doesn't allow from local. So I've clicked on "Set up Windows Azure firewall rules for this IP address" and added ip address. Now working fine when I run from local.
But When I tried to access from the iis8, I got an isssue is,
A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: TCP Provider, error: 0 - No such host is known.)
.Net SqlClient Data Provider.
In local, the same functionality is working fine.
Your server running IIS8 needs to be added to the firewall just like you did with your local machine, you can do this either using the Management Portal or you can connect to your SQL Azure instance from your local machine and run:
exec sp_set_firewall_rule N'IIS8 Webserver','X.Y.Z.0','X.Y.Z.0';
Where the first arguments is name of this firewall rule and X.Y.Z.0 is the public ip of your IIS8 Webserver.
The reason its specified two times is that you can specify a range of IP's.
More info here