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tiCrypt 2.18.1

Constellations

ResearcherRequires: Manager role on a constellation VM

A constellation is a virtual machine whose sole purpose is to manage a network of child VMs, called worker VMs. The constellation VM holds a list of worker templates, each naming a worker, its hardware setup, and its operating system, and it starts and stops the workers from those templates. A worker template is not a VM configuration: it lives inside the constellation and is managed from the constellation's VM Settings and Details, not from the VMs list.

Why constellations exist​

Some work needs several machines that act as one. A constellation lets the managers of one VM define, start, and stop a group of worker VMs without creating and sharing a separate VM configuration for each one. The constellation's VM Controller orchestrates the workers itself.

The worker list travels with the constellation. The VM Controller stores the worker templates in its database on the constellation's home drive, together with its users, groups, and access directories. The list therefore survives a restart of the constellation, like the rest of the VM's user database.

Whether a VM is a constellation is decided by its image, not by you. The constellation service is switched on in the configuration of the VM image, which the person who builds the image sets. A VM started from such an image reports the constellation service, and only then does tiCrypt show the Constellations section. You cannot turn an ordinary VM into a constellation from the web app; ask your admin for a hardware setup whose image provides it.

When to use a constellation​

  • Several workers for one project: use a constellation when a group of VMs should be started, stopped, and reached together from one place.
  • Workers with different operating systems: each worker template chooses Windows or Linux and its own hardware setup, so one constellation can hold both.
  • One machine is enough: use an ordinary VM configuration instead. See VM Configurations.

Before you begin​

  • The VM is running, you are connected to it, and its VM Controller reports the constellation service.
  • You have the Manager role on the VM, so you can open VM Settings and Details.
  • Your admin has published a hardware setup in the same realm as the constellation VM.

Open the constellation​

  1. Go to the Virtual Machines icon in the top left taskbar.
  2. Click the VMs section on the top left panel.
  3. In the left panel, click the running constellation VM.
  4. Click the VM Settings and Details option.
  5. In the new window, expand Misc. in the left panel and select Constellations.
Result:

The VM Constellation panel opens with the name of the VM and the number of worker VMs.

The toolbar offers Create worker template, Refresh, Filter workers..., and a selector that switches between a table and a list of the workers.

In table mode, the Active and Inactive choices switch between running and stopped workers. The table has the columns Name, Brick (the hardware setup), OS, and Actions. The following table describes the worker actions.

ActionDescription
Start workerStarts the worker VM. There is no confirmation.
Stop workerStops the worker VM. There is no confirmation.
Delete templateRemoves the worker from the constellation, after confirmation.
Start allStarts every inactive worker. There is no confirmation.
Stop allStops every active worker. There is no confirmation.

Create a worker template​

  1. In the VM Constellation panel, click Create worker template.
  2. In the Create new worker VM template for vm-name pop-up, enter a Name.
  3. Select a Hardware Setup. Only setups in the same realm as the constellation VM are offered.
  4. Select the Operating System: Windows or Linux.
  5. Click Create template.
Result:

The worker appears in the constellation's list of inactive workers. Start it with Start worker.

The name is required, can have up to 32 characters, must begin with a letter, and may contain only letters, digits, hyphens, underscores, and periods. It must differ from the names of the other workers in the constellation.

Delete a worker template​

  1. In the VM Constellation panel, click Delete template next to the worker.
  2. In the Remove worker-name from constellation? pop-up, read the warning: "The VM will be shut down immediately and all applications running on it will be stopped."
  3. Click Yes.
Result:

The worker VM is shut down if it was running, and its template is removed from the constellation.

Deleting a running worker stops its applications at once

The worker is shut down immediately. Save the work open on it before you delete its template.

Open an application on a worker​

The remote desktop of a constellation opens on one of its workers, not on the constellation VM.

  1. In the running VM panel of the constellation, click Start Remote Desktop.
  2. In the Connect to an application on vm-name pop-up, select a running worker. Each worker shows its operating system, cores, and RAM.
  3. Click Connect.
Result:

tiCrypt opens a tunnel to the worker and shows the credentials for the session. For the rest of the procedure, see Connect and Access.

On a constellation, managers can be given two extra VM permissions: Manage VPN and VM Orchestrator, which allows the management of the constellation. For more information, see VM Users.

Related

  • Connect and Access: start the constellation VM and open the remote desktop of a worker.
  • Advanced Operations: reach VM Settings and Details and the other management tools of a running VM.
  • VM Users: give managers the role and permissions they need to manage the constellation.
  • Submitting Jobs via Slurm: run batch work on worker VMs that Slurm creates for each job.