Introduction to Proxmox

Proxmox is an open-source virtualization platform based on Debian Linux, allowing users to run multiple virtual machines on a single physical host. It offers many advanced features, such as high availability, backup and restore, cluster management, and more. Proxmox supports various virtualization technologies, including KVM and LXC, and it also provides an easy-to-use web interface, enabling users to manage virtual machines, storage, and networks with ease. The main goal of Proxmox is to provide a powerful virtualization solution for both enterprise and individual users, while maintaining ease of use and reliability. In the Proxmox system, the “qm” command is the command-line tool for managing virtual machines, with key functionalities including creating, starting, stopping, deleting, cloning, migrating, backing up, and more.

Command Usage Examples

0. Command Syntax

The command refers to operations such as “create”, “stop”, “start” for virtual machines. The basic usage is “qm command vmid”, with different commands having different parameter options.

# qm <COMMAND> [ARGS] [OPTIONS]

1. List Virtual Machines

qm list

2. Create a Virtual Machine  

When creating a virtual machine, parameters such as memory size and CPU count need to be specified. The following command creates a virtual machine with 8GB memory, 2 cores, and a VM ID of 182. Since many parameters need to be set when creating a virtual machine, it is recommended to complete the creation through the graphical interface.

qm create –memory 8192 –sockets 1 –cores 2 182

3. Start a Virtual Machine  

qm start 180

4. Stop a Virtual Machine

qm stop 180

5. Check Virtual Machine Status

qm status 180

6. Unlock a Virtual Machine

If a virtual machine encounters errors during backup, cloning, migration, or snapshot operations, it may become locked, making it impossible to shut down or restart from the interface. To unlock the virtual machine, use the following command. If this command does not unlock it, you may need to delete the lock file under “/run/lock/qemu-server/lock-180.conf”.

qm unlock 180

7. Suspend a Virtual Machine

qm suspend 180

8. Resume a Virtual Machine  

qm resume 180

9. Reset a Virtual Machine  

qm reset 180

10. List Virtual Machine Snapshots

If you need to restore a virtual machine snapshot, you can first use `qm listsnapshot` to view the current snapshot list.

qm listsnapshot 180

11. Rollback Virtual Machine to a Specific Snapshot

12. View Virtual Machine Configuration Information

13. Delete a Virtual Machine

qm destroy 182

14. Create a Virtual Machine Snapshot

15. Delete a Snapshot  

16. Clone a Virtual Machine

17. Migrate a Virtual Machine to Another Node

First, check the names of the other nodes in the cluster, then execute the migration command. If there is local host configuration, such as a local CD-ROM configuration, you may encounter the error “can’t migrate local disk ‘local:iso/CentOS-8-x86_64-1905-dvd1.iso’: local cdrom image.” You can edit the configuration file to unmount the local ISO configuration, and then execute the migration command again.

18. Modify Virtual Machine Parameters

19. Enter Virtual Machine Monitor

Use the “qm monitor” command to enter the virtual machine console, where you can execute commands to view virtual machine information.