VM instance lifecycle  |  Compute Engine Documentation  |  Google Cloud (2024)

This document describes the lifecycle of a single virtual machine (VM)instance, starting from its creation through its potential deletion.

A VM instance can transition through many states as part of its lifecycle. Whenyou create a VM, Compute Engine provisions resources to start the VM.Next, the VM moves into staging, where it prepares for first boot. During andafter start-up, a VM is considered running. During its lifetime, a running VMcan be repeatedly stopped and restarted or suspended and resumed.

A VM can be in one of the following states:

• PROVISIONING: resources are allocated for the VM. The VMis not running yet.
• STAGING: resources are acquired, and the VM is preparing for first boot.
• RUNNING: the VM is booting up or running.
• STOPPING: the VM is being stopped. You requested a stop, or a failureoccurred. This is a temporary status after which the VM enters theTERMINATED status.
• REPAIRING: the VM is being repaired. Repairing occurs when the VMencounters an internal error or the underlying machine is unavailable due tomaintenance. During this time, the VM is unusable. You are not billed whena VM is in repair. VMs are not covered by theService level agreement(SLA) while they are in repair.If repair succeeds, the VM returns to one of the above states.
• TERMINATED: the VM is stopped. You stopped the VM, or the VMencountered a failure. You canrestartordelete the VM.
• SUSPENDING: The VM is in the process of being suspended. Yoususpended the VM.
• SUSPENDED: The VM is in a suspended state. You canresume the VM ordelete it.

The following diagram shows the transition between each VM state:

Stopping, suspending, or resetting a VM

You can stop or suspend a VM if you no longer need it but want to keep the VMfor future use. Your decision to stop or suspend a VM depends on whether youneed to preserve its guest OS memory and application state.

When you suspend or stop a VM, consider the following:

• You pay for resources that are still attached to a suspended or stopped VM,such as static IPs and persistent disk data. For more information, see the pricing guide.
• Ephemeral external IP addresses are released from the VM. When you restartor resume the VM, Google assigns new ephemeral external IP addresses. Ifyou depend on an ephemeral external IP address remaining the same throughrestarts,promote the ephemeral external IP addressto a static IP address.
• Static external IP addresses are retained.

Stopping a VM

Stopping a VM causesCompute Engine to send the ACPI shutdown signal to the VM.Modern guest operating systems are configured to perform a clean shutdown beforepowering off in response to the power off signal. Compute Engine waitsa short time for the guest to finish shutting down and then transitions theVM to the TERMINATED state.

You might want to stop a VM for several reasons:

• You no longer need the VM but want the resources that are attached to theVM—such as its internal IPs, MAC address, and persistent disk.
• You don't need to preserve the guest OS memory, device state, or applicationstate.
• You want to change certain properties of the VM that require you to firststop the VM.

You can restart a terminated VMwhen you need to use it again.

Suspending a VM

Suspending a VM sends anACPI S3 suspend signal to the VM's operating system. Suspending a VM isanalogous to closing the lid of your laptop or putting the VM into a suspendedstate. When you suspend a VM, it transitions to the SUSPENDED state.

You might want to suspend a VM for the following reasons:

• You want to stop paying for the core and memory costs of running a VM andpay the comparatively cheaper cost of storage to preserve the state of yourVM instead.
• You don't need the VM at this time but want to be able to bring itback up quickly with its OS and application state where you left it.

You can resume a suspended VMwhen you need to use it again.

Resetting a VM

Alternatively, you canreset a VMto wipe the memory contents of the VM and reset the VM to its initial state.Resetting a VM causes an immediate hard reset of the VM; the VM doesn't do agraceful shutdown of the guest OS. However, the VM retains all persistentdisk data, and none of the VM properties change. The VM remains in the RUNNINGstate through the reset.

Comparison table

The following table shows how stopping, suspending, and resetting a VM affectsthe VM and its resources:

Checking a VM's status

Every VM reports its status as part of the VM's properties. Check a VM's statusin the following circ*mstances:

• You are experiencing issues with the VM.
• You just started the VM and want to confirm that the VM is running.
• You want to confirm that the VM has been suspended or stopped(that is, in the SUSPENDED or TERMINATED state).

To list all VMs and their statuses, use the following command:

gcloud compute instances list

To describe the status of a single instance, use this command:

gcloud compute instances describe example-instance

Hardware failure

Rarely, a VM might fail due to an unexpected outage, hardware error, or anothersystem issue. Mitigate hardware failure by using persistent disks, routinelybacking up your data, and designing your system so that a single VM failure isnot catastrophic. For more information, see Designing robustsystems.

If a VM fails, it is restarted automatically with the same rootpersistent disk, metadata, and VM settings. To modify the automatic restartbehavior, see Setting instance availabilitypolicies.

What's next

• Learn more aboutlive migration during maintenance events.
• Learn how tosuspend or resume a VM.
• Learn how tostop or restart a VM.
• Learn how toreset a VM.
• Learn how to delete a VM.