Cannot Connect To SQL Within Azure Network - sql-server

I am having a real hard time establishing SQL connection between servers within a Azure network. The really odd thing is that I can connect to SQL from my home machine which is outside the VM network. It seems like some type of network issue from within the VM domain which I have not been able to identify yet.
My configuration is as follows:
I have three VM's (Active Directory, Sql Server, and an App Server)
I am trying to establish SQL connection from app server to sql server
Both VM's Windows Server 2012
All servers are on the same azure network, affinity group, domain
All servers connected to the domain and have IP's
I can see DNS is resolving because I can ping the sql server from the app server using the sql server's computer name
I created Firewall rules allowing in/out on port 1433 on both servers
SQL Server is listening on the default port because of this command executed on the SQL Server (i'm not understanding the 0.0.0.0 IP though which may be a problem) (I can connect from home so I think this is ok)
netstat -an | find ":1433"
TCP 0.0.0.0:1433 0.0.0.0:0 LISTENING
TCP [::]:1433 [::]:0 LISTENING
I created public & private endpoints on SQL for default sql port 1433
I can actually connect to SQL Server from my home machine
I have temporarily turned off firewalls on both servers
tracert from the app server looks like this.
tracert spsql01
Tracing route to spsql01 [10.0.0.7]
over a maximum of 30 hops:
1 * * * Request timed out.
2 * * * Request timed out.
3 * * * Request timed out.
4 5 ms <1 ms 1 ms spsql01 [10.0.0.7]
Trace complete.
On the App Server i create a connection.udl file to test the connection to my SQL Server but it never passes the connection test.

Have you created the appropriate Windows Azure SQL Database firewall rules for your VMs in Windows Azure? You can use either the special 0.0.0.0 for all of Windows Azure or, better, provide the public VIP of your IaaS cloud service (not the private DIP of the individual VMs). The latter limits firewall access to only your cloud service, since the outbound connection to WASD will use your public VIP. Note that if you delete (or stop/deallocate) all the VMs in your cloud service you will lose the VIP.

Related

Unable to access Azure SQL Server from Azure VM

Following the Azure VM cluster tutorial provided by Microsoft (https://learn.microsoft.com/en-us/azure/developer/terraform/create-vm-cluster-with-infrastructure),
I have a resource group created in Azure.
Under the Resource group, I have created VN, subnets, etc.
Now, I have two VMs created in the resources group. Both of them have a LoadBalancer on top. I have added NAT rule to LB to connect to individual instance, while they both share the same frontend IP.
I have created a new resource Azure MSSQL server, in the Firewall rule of the SQL server, added the public ip of the LB to the Azure Server
I have now logged in to the individual VMs, and tried to access the SQL server from the VM, but I am unable to connect to it.
I tried normal ping <hostname>
it fails 133 packets transmitted, 0 received, 100% packet loss, time 295ms
Then I try telnet from IP address (ip address was received from ping )
and I get
Trying <ip_address>...
Connected to <ip_address>.
Escape character is '^]'.
When I try to connect using an application, I get this error
com.microsoft.sqlserver.jdbc.SQLServerException: Connection reset ClientConnectionId:8b2f0e3b
-fda0-41af-b8dc-ce80d0760b82
at com.microsoft.sqlserver.jdbc.SQLServerConnection.terminate(SQLServerConnection.jav
a:3806) ~[mssql-jdbc-11.2.0.jre8.jar:?]
at com.microsoft.sqlserver.jdbc.TDSChannel.read(IOBuffer.java:2109) ~[mssql-jdbc-11.2
.0.jre8.jar:?]
at com.microsoft.sqlserver.jdbc.SQLServerConnection.prelogin(SQLServerConnection.java
:3517) ~[mssql-jdbc-11.2.0.jre8.jar:?]
at com.microsoft.sqlserver.jdbc.SQLServerConnection.connectHelper(SQLServerConnection
.java:3325) ~[mssql-jdbc-11.2.0.jre8.jar:?]
at com.microsoft.sqlserver.jdbc.SQLServerConnection.login(SQLServerConnection.java:29
50) ~[mssql-jdbc-11.2.0.jre8.jar:?]
at com.microsoft.sqlserver.jdbc.SQLServerConnection.connectInternal(SQLServerConnecti
on.java:2790) ~[mssql-jdbc-11.2.0.jre8.jar:?]
at com.microsoft.sqlserver.jdbc.SQLServerConnection.connect(SQLServerConnection.java:
1663) ~[mssql-jdbc-11.2.0.jre8.jar:?]
at com.microsoft.sqlserver.jdbc.SQLServerDriver.connect(SQLServerDriver.java:1064) ~[
mssql-jdbc-11.2.0.jre8.jar:?]
at jet.server.db.core.ConnectorManager$ConnectionPool.£(ConnectorManager.java:712) ~[
JRESServlets.jar:?]
at jet.server.db.core.ConnectorManager$ConnectionPool.connect(ConnectorManager.java:4
32) ~[JRESServlets.jar:?]
at jet.server.db.core.ConnectorManager$ConnectionPool.getConnection(ConnectorManager.
java:504) ~[JRESServlets.jar:?]
at jet.server.db.core.ConnectorManager$ConnectionPool.getConnection(ConnectorManager.
java:487) ~[JRESServlets.jar:?]
at jet.server.db.core.DatabaseImpl.open(DatabaseImpl.java:839) ~[JRESServlets.jar:?]
at jet.server.db.core.GlobalDataService.<init>(GlobalDataService.java:103) ~[JRESServ
lets.jar:?]
at jet.server.db.core.GlobalDataService.init(GlobalDataService.java:37) ~[JRESServlet
s.jar:?]
at jet.server.ServerEnv.K(ServerEnv.java:2322) ~[JRESServlets.jar:?]
How do I make this work?
Azure SQL is only available through TCP port 1433. Check whether firewall is allowed outgoing TCP communication on port 1433.
You can check the connection by using below command:
Test-NetConnection -Port 1433 -ComputerName ServerName.database.windows.net
To resolve the error, make sure to open firewall in the path from Server like Windows Firewall, Corporate Firewall or Azure NSG (Network security group to allow access.
In the Azure SQL Server, select Networking and enable the below option:
Connect to the Azure Virtual Machine and restart SQL Server like below:
Reference:
IP firewall rules - Azure SQL Database | Microsoft Learn

SQL Connection from Azure Linux App Service web app

I have an asp net core web app and SQL Server database hosted in Plesk via a hosting company.
I have deployed a copy of the web app to an Azure Linux App Service. It uses the Plesk hosted SQL Server database. When i use the Azure App Service I get a connection error when accessing the Plesk hosted database.
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: TCP Provider, error: 40 - Could not open a connection to SQL Server)
If I use the Plesk hosted web app it connects to sql server correctly as expected. If I then immediately use the Azure Linux web app it manages to get a SQL connection! In all cases the connection string is identical. Its like it needs waking up!
How can this be the case. I am at a loss as to why this is happens. Any ideas folks?
Properly, you need to add the outbound IP addresses in Azure App Service into the firewall of SQL Server which your SQL Server database existed.
edit
You could check the following aspects on your side refer to this.
Make sure SQL Server Service is running
If a named instance, make sure SQL Server browser service is running
Make sure SQL Server is configured to allow remote connections
Examine the SQL Server error log for messages confirming that SQL is listening on the expected network interfaces and ports
Test server connectivity with PING from the client machine
Test port connectivity using TELNET or PowerShell to the server and port (from step 4) from the client machine. For example a. TELNET
1433 b. PowerShell: 1433 | % { echo ((new-object
Net.Sockets.TcpClient).Connect("YourServerName",$)) "server listening
on TCP port $" }
Check firewall settings if step 5 or 6 connectivity test fails
For more information:
Troubleshoot connecting to the SQL Server Database Engine
Networking Related Commands for Azure App Services

Unable to telnet to SQL mirroring port on public IP on Azure ARM VM

I am trying to mirror a on premise SQL database to Azure ARM VMs running SQL server. One for the mirror and one for the witness. I have setup the mirroring end points on the servers. However, I am getting an error to the effect that the mirror server can not be reached.
Reading through the net pages, I tested the port using telnet. I am able to telnet to the mirroring port on my local server from the Azure VM but unable to telnet from the local server to the VMs.
I am able to telnet on the mirroring port between the VMs using the Private IP Address but unable to do so using the Public IP address.
I have added the port to the Security group being used by these VMs to allow inbound connections as well as outbound connections.
I have tested that the server is listening on ip 0.0.0.0 and my mirroring port.
Any help would be very much appreciated.
For whatever its worth, I was setting the Inbound connections source port range as the port I was going to use for mirroring. I changed this to "*" and it started working.

Azure - Network Path Not Found

I have 4 Azure VMs which are part of the same resource group and virtual network. 3 of them are running SQL Sever and 1 of them is configured as a domain controller. The 3 SQL VMs are getting there DNS from the DC.
The VMs can log into the domain and see each other on the network. When I try to use connect to SQL instances across the virtual network, however, I receive a network path not found error.
I have renamed the instances and even tried removing and re-installing them. So I am sure it is a network issue, and not a SQL Server problem. I also can't connect via IP address, so it doesn't seem to be DNS.
The instances are all default instances and are connected on 1433, the VMs all have TCP 1433 endpoints and Windows Firewall is turned off.
I think you need to Enable the Port from Azure Services As well
The instances are all default instances and are connected on 1434, the
VMs all have TCP 1433 endpoints, and Windows Firewall is turned off.
Ensure you have both ports open in all machines. 1433, 1434
Also remember that disable windows firewall is just a temporary thing, you should re-enable it once the connection test pass.
Note that depending of your kind of connection/services you also should open:
1433: / TCP / UDP
80: For sync over HTTP / TCP
443: SQL Server default instance running over an HTTPS endpoint / TCP
4022: Service Broker / TCP
135: Transact-SQL debugger / TCP
7022: Defacto database mirroring / TCP
2383: SQL Server Analysis Services
2382: connection requests to a named instance of Analysis Services

Use SQL Server Management Studio to connect remotely to an SQL Server Express instance hosted on an Azure Virtual Machine

Initial Attempt
I have an Azure VM with Windows Server 2012, on which I just installed SQL Server 2012 Express Database Engine component. Then, I followed the instructions here to connect remotely with SQL Server Management Studio.
Create a TCP endpoint for the virtual machine
Open TCP ports in the Windows firewall
Configure SQL Server to listen on the TCP protocol
Configure SQL Server for mixed mode authentication
Create SQL Server authentication logins
Determine the DNS name of the virtual machine
Connect to the Database Engine from another computer
After step seven I received the following error:
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)
(Microsoft SQL Server, Error: 53)
What else do I need to configure before connecting remotely?
Troubleshooting
I have been following the troubleshooting instructions here. Each blockquote below is a step described that that link.
Confirm the instance of the SQL Server Database Engine is installed
and running.
Done. We installed SQL Server Express, and it is running as a named instance called SQLEXPRESS.
If you are attempting to connect to a named instance, make sure the
SQL Server Browser service is running.
Done. We followed the steps here to turn on the SQL Server Browser service.
Get the IP Address of the computer.
Done. We will use these later for testing connectivity and maybe for setting up a static port for SQLEXPRESS.
10.241.62.155
fe80::45c:8c29:e19f:f78b%15
Get the TCP port number used by SQL Server.
Done. The SQL Server Management Studio server logs showed that the server was listening on port 49169.
Enable Protocols
Done. We had already enabled TCP/IP in the configuration manager, but we restarted the SQL Server Service just in case.
Testing TCP/IP Connectivity
Done. We used tcping.exe to test connectivity (cmd ping doesn't work quickly with Azure.) We were able to connect to port 80.
tcping.exe buddha.cloudapp.net > successful
tcping.exe buddha.cloudapp.net 80 > successful
Testing a Local Connection
Done. We used sqlcmd.exe from the command prompt and were able to connect locally via TCP with a username and password.
sqlcmd -S Buddha\SQLEXPRESS (success via shared memory protocol)
sqlcmd -S tcp:Buddha\SQLEXPRESS (success via TCP)
sqlcmd -S tcp:Buddha\SQLEXPRESS -U sa -P (success via TCP with username)
sqlcmd -S tcp:10.241.62.155\SQLEXPRESS -U sa -P (success with internal IP)
Opening a Port in the Firewall
We opened the port on which we SQLEXPRESS listens. The server logs (above) showed that SQLEXPRESS was listening on port 49169, but this is just one of many dynamic ports, and we wanted to set up the static port 1435.
Use WF.msc to create an inbound TCP rule for port 1435.
Use Azure Management Portal to create a TCP endpoint for port 1435.
The troubleshooting instructions also say:
If you are connecting to a named instance or a port other than TCP
port 1433, you must also open the UDP port 1434 for the SQL Server
Browser service.
Since we are connecting SQLEXPRESS (a named instance), we needed to open port 1434 for UDP.
Use WF.msc to create an inbound UCP rule for port 1434.
Use Azure Management Portal to create a UDP endpoint for port 1434
Further research about connecting to named instances revealed dynamic port issues. The reason why we are using port 1435 (static) instead of port 49169 (one of many effective options.)
Instances of SQL Server Express, SQL Server Compact, and named
instances of the Database Engine use dynamic ports. To configure these
instances to use a specific port, see Configure a Server to Listen on
a Specific TCP Port (SQL Server Configuration Manager). and
here.
Done. We went to SQL Configuration Manager > SQL Server Network Configuration > Protocols for SQLEXPRESS > TCP/IP, we did the following.
Protocol Tab > Listen All > NO.
IP Addresses Tab > for each listed address
Enabled > Yes
TCP Dynamic Ports > Blank (delete the zero)
TCP Port > 1435 (or your choice)
After restarting the SQLEXPRESS service, we again looked in the SQL Server Management Studio logs, and found that the Server is Listening on port 1435!!! Hooray!
Testing the Connection
Done. We opened SQL Server Management Studio on our local (non-Azure) computer and connected.
buddha.cloudapp.net,1435 OR buddha.cloudapp.net\SQLEXPRESS
sa
password
Success.
Here are the three web pages on which we found the answer. The most difficult part was setting up static ports for SQLEXPRESS.
Provisioning a SQL Server Virtual Machine on Windows Azure. These initial instructions provided 25% of the answer.
How to Troubleshoot Connecting to the SQL Server Database Engine. Reading this carefully provided another 50% of the answer.
How to configure SQL server to listen on different ports on different IP addresses?. This enabled setting up static ports for named instances (eg SQLEXPRESS.) It took us the final 25% of the way to the answer.
The fact that you're getting an error from the Names Pipes Provider tells us that you're not using the TCP/IP protocol when you're trying to establish the connection. Try adding the "tcp" prefix and specifying the port number:
tcp:name.cloudapp.net,1433
I too struggled with something similar. My guess is your actual problem is connecting to a SQL Express instance running on a different machine. The steps to do this can be summarized as follows:
Ensure SQL Express is configured for SQL Authentication as well as Windows Authentication (the default). You do this via SQL Server Management Studio (SSMS) Server Properties/Security
In SSMS create a new login called "sqlUser", say, with a suitable password, "sql", say. Ensure this new login is set for SQL Authentication, not Windows Authentication. SSMS Server Security/Logins/Properties/General. Also ensure "Enforce password policy" is unchecked
Under Properties/Server Roles ensure this new user has the "sysadmin" role
In SQL Server Configuration Manager SSCM (search for SQLServerManagerxx.msc file in Windows\SysWOW64 if you can't find SSCM) under SQL Server Network Configuration/Protocols for SQLExpress make sure TCP/IP is enabled. You can disable Named Pipes if you want
Right-click protocol TCP/IP and on the IPAddresses tab, ensure every one of the IP addresses is set to Enabled Yes, and TCP Port 1433 (this is the default port for SQL Server)
In Windows Firewall (WF.msc) create two new Inbound Rules - one for SQL Server and another for SQL Browser Service. For SQL Server you need to open TCP Port 1433 (if you are using the default port for SQL Server) and very importantly for the SQL Browser Service you need to open UDP Port 1434. Name these two rules suitably in your firewall
Stop and restart the SQL Server Service using either SSCM or the Services.msc snap-in
In the Services.msc snap-in make sure SQL Browser Service Startup Type is Automatic and then start this service
At this point you should be able to connect remotely, using SQL Authentication, user "sqlUser" password "sql" to the SQL Express instance configured as above. A final tip and easy way to check this out is to create an empty text file with the .UDL extension, say "Test.UDL" on your desktop. Double-clicking to edit this file invokes the Microsoft Data Link Properties dialog with which you can quickly test your remote SQL connection

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