Cannot connect to docker in Azure Pipelines - azure

Question

In my Azure Pipeline I created a container using docker run using the below command:
docker run -e 'ACCEPT_EULA=Y' -e 'SA_PASSWORD=Pa$$w0rd12' -p 1433:1433 -d mcr.microsoft.com/mssql/server:2017-latest-ubuntu
In another task I tried listing this container with a docker ps and it shows me the container as below:
/usr/bin/docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
afca60eb6fde mcr.microsoft.com/mssql/server:2017-latest-ubuntu "/opt/mssql/bin/nonr…" 1 second ago Up Less than a second 0.0.0.0:1433->1433/tcp, :::1433->1433/tcp nostalgic_jemison
Finishing: list docker containers
Post that I'm trying to run my dotnet integration tests which uses the above container for the SQL server. These tests are supposed to create their own DB inside the servers, run the tests and delete them. But It fails while running the tests with the below error:
Error Message:
System.AggregateException : One or more errors occurred. (A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: TCP Provider, error: 40 - Could not open a connection to SQL Server)) (The following constructor parameters did not have matching fixture data: DatabaseSetup databaseSetup)
---- Microsoft.Data.SqlClient.SqlException : A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: TCP Provider, error: 40 - Could not open a connection to SQL Server)
---- The following constructor parameters did not have matching fixture data: DatabaseSetup databaseSetup
The connection string I'm using in the integration tests are as below:
"Data Source=localhost,1433;Initial Catalog=dbname;User Id=SA;Password=Pa$$w0rd12"
I'm using Ubuntu 20.04 as the build agent. Same setup works fine on my local system on WSL with Ubuntu20.04
Update 1: I have replaced localhost with the IP address of the container in connection string. Works fine in WSL locally but it still throws the same error on Azure Pipelines.
Update 2: I have just noticed that the container stops when I run dotnet test in the pipeline. I can see container running before dotnet test but can't see the container active after dotnet test

Answer 1

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)
You can follow the below steps to troubleshoot the error:
Verify that the instance is running
Verify that the SQL Server Browser service is running
Verify the server name in the connection string
Verify the aliases on the client machines
Verify the firewall configuration
Verify the enabled protocols on SQL Server
Test TCP/IP connectivity
Test local connection
Test remote connection
The following constructor parameters did not have matching fixture
data: DatabaseSetup databaseSetup
You can refer to The following constructor parameters did not have matching fixture data for more help.