xl

xl Command

The xl command is a tool used to manage Xen virtual machines (VMs) and is part of the Xen hypervisor suite. It provides an interface to create, manage, and control virtual machines running on a Xen system. The xl command replaces older tools like xm and is intended to be a simpler, more powerful command-line tool for managing Xen guests.

Key Features of the xl Command

  • VM Management: xl provides commands for creating, starting, stopping, and managing virtual machines on a Xen hypervisor.

  • Resource Allocation: It allows you to allocate resources like CPU, memory, and disk to virtual machines.

  • Networking Configuration: You can manage network interfaces and configure how the VM will connect to the network.

  • Snapshotting and Migration: It supports taking snapshots of virtual machines and migrating VMs between hosts.

  • VM Monitoring: xl offers commands for monitoring VM status and retrieving information about virtual machines.

Common xl Subcommands

Here are some of the most commonly used subcommands of the xl tool:

1. xl create

  • Creates a new virtual machine from a configuration file.

  • Syntax: xl create <config_file>

  • Example:

    xl create /path/to/vm.cfg

2. xl list

  • Lists all running virtual machines along with their statuses.

  • Syntax: xl list

  • Example:

    xl list

Output example:

Name           ID   Mem VCPUs State   Time(s)
vm1            1    2048 2     r-----   123.4
vm2            2    1024 1     -b----   50.7

3. xl start

  • Starts an existing virtual machine that has been previously created but is not running.

  • Syntax: xl start <vm_name>

  • Example:

    xl start vm1

4. xl shutdown

  • Initiates a clean shutdown of a virtual machine.

  • Syntax: xl shutdown <vm_name>

  • Example:

    xl shutdown vm1

5. xl destroy

  • Forcefully shuts down a virtual machine (equivalent to power off).

  • Syntax: xl destroy <vm_name>

  • Example:

    xl destroy vm1

6. xl suspend

  • Suspends the execution of a virtual machine (pauses it).

  • Syntax: xl suspend <vm_name>

  • Example:

    xl suspend vm1

7. xl resume

  • Resumes a suspended virtual machine.

  • Syntax: xl resume <vm_name>

  • Example:

    xl resume vm1

8. xl reboot

  • Reboots a virtual machine.

  • Syntax: xl reboot <vm_name>

  • Example:

    xl reboot vm1

9. xl info

  • Provides detailed information about the Xen hypervisor, such as memory, CPU, and other statistics.

  • Syntax: xl info

  • Example:

    xl info

Output example:

host: example_host
release: 4.12.0
cpu-model: Intel Xeon E5-2690 v4
memory: 32000MB

10. xl migrate

  • Migrates a virtual machine from one host to another.

  • Syntax: xl migrate <vm_name> <destination_host>

  • Example:

    xl migrate vm1 xen1

11. xl console

  • Connects to the virtual console of a running virtual machine.

  • Syntax: xl console <vm_name>

  • Example:

    xl console vm1

12. xl save

  • Saves the state of a virtual machine, allowing it to be restored later.

  • Syntax: xl save <vm_name> <save_file>

  • Example:

    xl save vm1 /path/to/savefile

13. xl restore

  • Restores the state of a virtual machine from a saved file.

  • Syntax: xl restore <save_file>

  • Example:

    xl restore /path/to/savefile

14. xl create

  • Creates and starts a virtual machine based on a configuration file.

  • Syntax: xl create <config_file>

  • Example:

    xl create /path/to/vm1.cfg

Example Workflow Using xl

  1. Create a new virtual machine: Define the configuration for a VM in a configuration file (vm1.cfg), and then create it using the xl create command.

    xl create /path/to/vm1.cfg
  2. List all running virtual machines: To see which VMs are currently running and their statuses, use:

    xl list
  3. Start a VM: To start a VM that has been created but is not running, use:

    xl start vm1
  4. Shutdown a VM: When you need to cleanly shut down a running virtual machine:

    xl shutdown vm1
  5. Check Hypervisor Information: To view information about the Xen hypervisor:

    xl info

Conclusion

The xl command is a versatile and essential tool for managing Xen virtual machines. It allows administrators to create, monitor, control, and configure VMs on the Xen hypervisor. Whether you're starting and stopping VMs, allocating resources, or monitoring the system, xl simplifies virtual machine management and provides an efficient interface for interacting with Xen hypervisor features.

Last updated