c# - .Net Core 3.1 MSSQL backend in Docker setup: Docker-compose up producing connection failure

Question

docker-compose.yml version: "3.9" services: web: build: . ports: - "8000:80" container_name: web_application depends_on: - medicalmgr

medicalmgr:
    image: "mcr.microsoft.com/mssql/server:2019-latest"
    environment:
        SA_PASSWORD: Pw@mm2021
        ACCEPT_EULA: Y
    ports:
        - "1433:1433"
    container_name: mmm_mmsql_2019

dockerfile

FROM mcr.microsoft.com/dotnet/core/sdk:3.1 AS build-env WORKDIR /app COPY . . RUN dotnet restore &&
dotnet publish -c Release -o out

Build runtime image

FROM mcr.microsoft.com/dotnet/core/aspnet:3.1 WORKDIR /app COPY --from=build-env /app/out . ENTRYPOINT ["dotnet", "MedicalManager.dll"]

Startup.cs 's public void CofigureServices(..){ .... var server = Configuration["DBServer"] ?? "medicalmgr"; var port = Configuration["DBPort"] ?? "1433"; var user = Configuration["DBUser"] ?? "SA"; var password = Configuration["DBPassword"] ?? "Pw@mm2021"; var database = Configuration["Database"] ?? "MedicalManager";

   //var connectionStr = $"Server={server},{port};Initial Catalog={database};User ID= 
   //{user};Password={password}";
   var connectionStr = 
   @"Server=medicalmgr;Database=MedicalManager;User=sa;Password=Pw@mm2021;";
   services.AddDbContext<MedicalManagerDBContext>(
            options => options.UseSqlServer(connectionStr)
   );}

Error: Application startup exception: Microsoft.Data.SqlClient.SqlException (0x80131904): 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)

Answer 1

等待大神解答