Docker to Docker ECONNREFUSED (Node-Red - to - SQL Server)

General
1

I have a Windows System.
Inside the Windows System, I have Virtual Box with Ubuntu
Inside the Ubuntu, I have installed Node-Red and SQL Server as dockers.

While being inside the Ubuntu,
I am able to work with Node-Red via localhost:1880
I am able to work with SQL-Server via localhost:1433 or 127.0.0.1 or 127.17.0.03:1433 or 127.18.0.3:1433 using the Azure Data Studio for Linux.

Considering the previous status, Node-Red & SQL Server are up and running, now i am trying to write from Node-Red to SQL Server table.

I have tried to use the MSSQL Node from node-red-contrib-mssql-plus:

  • using localhost:1433, I am getting: Failed to connect to localhost:1433 Could not connect (sequence)

  • using 127.0.0.1:1433, I am getting: Failed to connect to 127.0.0.1:1433 connect ECONNREFUSED 127.0.0.1:1433

  • using 127.17.0.3:1433, I am getting: Failed to connect to 127.17.0.3:1433 connect ECONNREFUSED 127.17.0.3:1433

  • using 127.18.0.3:1433, I am getting: Failed to connect to 127.18.0.3:1433 connect ECONNREFUSED 127.18.0.3:1433

I tried both with SA and with a user I created, both are working via Azure Data Studio
In addition, I have tried to add a bridge between these two containers and connect them in this new network.

Also noticed that if I try with 14XX I get the same error, and if I try with SQL stopped again I get the same error. Security issue? But why Azure studio have not a problem?
What I am missing?

----Update----
If I configure the mssql-node with the name of the container of the MSSQL is working.

  • Hostname: sql1
  • Port: 1433

Still not sure why its not working with ips

2

I am almost certain this is a docker setup issue.
You probably need to search "docker to docker communication" or ask on a docker forum I think (unless some docker wiz picks this question up)

I'm gonna edit the title so it gets correct exposure.

3

Yes you probably need to setup the docker networking correctly so that the simple name resolution will work. We have an example in the docs.

4

After so many hours, I figured out that if I configure the mssql-node with the name of the container of the MSSQL is working.

  • Hostname: sql1
  • Port: 1433

Still not sure why it's not working with ips

5

Hi, maybe the reason the Azure Studio is able to communicate, is because is installed in the host (Ubuntu)?

I tried to ping those different IPs/Ports and none of them are working, the only working IPs/Ports are:

  • localhost:1880 (NODERED)

  • 127.17.0.2:1880 (NODERED)

  • 127.18.0.2:1880 (NODERED)

  • sql1:1433 (SQL)