vagrant-suspend

Suspend the currently running machine

$ vagrant suspend

$ vagrant suspend [name|id]

vagrant suspend [options] [name]

--force, -f
    Forces the suspension of the machine, even if there are problems or errors encountered during the process. This can be useful in situations where a clean suspension isn't possible due to an unstable state.

[name]
    Specifies the name of a specific machine to suspend in a multi-machine Vagrant environment. If omitted, Vagrant will attempt to suspend all currently running machines defined in the `Vagrantfile`.

The `vagrant suspend` command saves the current running state of a Vagrant virtual machine to disk. This is analogous to putting a computer into hibernation or sleep mode. When a machine is suspended, its memory contents, CPU state, and device states are written to persistent storage, allowing the machine to be resumed later exactly where it left off, without the need for a full boot sequence. This is particularly useful for quickly freeing up system resources without losing work or context, enabling developers to switch between projects or conserve battery life on laptops.

Unlike `vagrant halt`, which performs a graceful shutdown of the guest operating system, `suspend` preserves the exact live state, making startup much faster upon vagrant resume. However, it requires disk space to store this state and can sometimes be less robust than a full shutdown and boot if the environment is unstable.

Disk Space Usage: Suspending a machine requires disk space on the host system, typically equivalent to the machine's allocated RAM, to store its saved state. Ensure sufficient free space.
Provider Compatibility: The reliability and performance of suspension can vary significantly between different virtualization providers (e.g., VirtualBox, VMware) and guest operating systems.
Potential for Corruption: In rare cases, especially with complex or unstable guest environments, suspending and resuming can lead to minor state corruption or unexpected behavior within the guest OS.
Network Interruptions: Upon resuming a suspended machine, network connections inside the guest may need to be re-established, which can cause brief service interruptions.

When `vagrant suspend` is executed, it delegates the actual suspension process to the configured virtualization provider (e.g., VirtualBox, VMware, Hyper-V). The provider then captures the entire current memory and CPU state of the virtual machine, along with the state of its virtual devices, and writes this information to a special 'saved state' file on the host system's disk. This file allows the VM to be later restored to that exact point in time, bypassing the need for a full boot sequence.

In `Vagrantfile` configurations that define multiple virtual machines, invoking `vagrant suspend` without specifying a machine name will prompt Vagrant to attempt to suspend all currently running machines defined within that `Vagrantfile`. To target a specific machine, simply provide its assigned name as an argument, for example, `vagrant suspend webserver`.

The `suspend` command has been a fundamental component of Vagrant since its early versions, reflecting the developer's need for efficient lifecycle management of development environments. Its inclusion underscores the importance of quick context switching and resource optimization, akin to hibernation features in host operating systems. The command's implementation relies on the underlying virtualization provider's capabilities, evolving as these providers enhance their state-saving mechanisms and stability.

vagrant resume(1), vagrant halt(1), vagrant destroy(1), vagrant up(1)