Yeah, I forgot about docker. But it is possible to solve this as well. 

Connect to the instance with SSH in any way offered by Google.

cd /opt/ISC
sudo vi docker-compose.yml

So, you can now add more ports. Save it (:wq)))

sudo docker-compose up -d

Do not forget to configure firewall rules.

You can even add this line, and remove ports block at all, and get access to any future ports without a restart container.

network_mode: host

Mike, thanks for the feedback.

Questions about passwords were raised privately. But mostly about secure storage. Your case very different, and even maybe better way, to have SSO instead of storing passwords. It will need some research, but I'm sure it will be possible to implement it. As a company CaretDev, I would like to offer commercial support to your company. So, it will be easier to find time to implement any features, you would like to have.

About toggle between namespaces. I don't know why do you need it, and how you going to use it. The main point of VSCode is sources stored locally, when you will toggle namespace, how you going to keep namespaces correctly updated?

Or you can use a server-side editing feature. You can create file myapp.code-workspace in the root of your project, press button Open workspace. And you will have connection to USER and %SYS namespaces as well, so, just add more isfs URLs with ns=NAMESPACE.

{
  "folders": [
    {
      "name": "myapp",
      "path": ".",
    },
    {
      "uri": "isfs://myapp",
      "name": "server",
    },
    {
      "uri": "isfs://myapp?ns=USER",
      "name": "user",
    },
    {
      "uri": "isfs://myapp?ns=%SYS",
      "name": "system",
    }
  ],
  "settings": {
    "files.exclude": {},
    "objectscript.conn": {
      "active": true,
      "username": "_system",
      "password": "SYS",
      "ns": "MYAPP",
      "port": 52773,
    },
    "objectscript.serverSideEditing": true
  }
}

Unfortunately, I don't have yet, any good solution for now, as store your sources in XML format. You can export them with /exportversion=cache2018.1  flag, with your Studio SourceControl class. IRIS will upgrade source code for Caché and downgrade when you export them with the flag.

Btw, you can have sources in XML and use the modern VSCode-ObjectScript editor.

It's just a default empty instance. You then have to create a new namespace with the database. Interoperability will be enabled by default in that new Namespace, and it will appear there. But, you should have in mind, that all those changes may disappear by default, when you delete your container and start it again, it will be the same as in the first start. You can configure durable %SYS, to get it stored outside of the container or volumes.

You can deploy IRIS with Kubernetes which is inside of OpenShift. It is not so easy to explain here. As it will be just a common task, rather than something narrow just for you. Deploying a database to the cluster is a very specific task, and very depends on your needs.

As well as Kubernetes, I think you may also use ICM, did not use it before, so, not sure if it will work with OpenShift as well.

Sharding will allow you to split your data between physically different servers with each own storage. So, you may get faster simultaneous read/write of data. At the same time with ECP configuration, your application servers will get direct access to the sharding node which holds data. 

So, if it is correctly configured you should get some profit from it, for sure.

Studio Uses Super port to connect to DB. And keep connected all the time, when it loses connection it offers to even restart Studio not just reconnect. It can also hang when you doing a big compile.

I would recommend finding a way to migrate to the latest version. And so, you will be able to use VSCode-ObjectScript, which does not care about connection status, you can restart the server, you can do debug and big compile.

If you provisioned IRIS on Google Cloud from marketplace, you should be able to see the same page as on my screenshot. You can press the button Visit the site, which will go you to System Management Portal, where you should be able to login with the default _SYSTEM and SYS, after that it will request you to change the default password. Which you can use in VSCode or Atelier. 

Using VSCode-ObjectScript is very easy to connect to a cloud instance with IRIS.

 Just Use IP address and port from site address, login _SYSTEM and password changed after first connect. 

And write it to file, .vscode/settings.json in your project folder

{
    "objectscript.conn": {
        "active": true,
        "host": "xx.xx.xx.xx",
        "port": 52773,
        "username": "_SYSTEM",
        "password": "123",
        "ns": "USER",
    }    
}