Proxmox Virtualization System

Proxmox Virtual Environment (PVE) is an open-source virtualization system based on Debian GNU/Linux. It is developed by the Austrian company Proxmox Server Solutions GmbH, sponsored by Internet Foundation Austria. It uses KVM and LXC as its hypervisors.

LXC (Linux Containers) is an operating-system-level virtualization system for running multiple isolated Linux instances on a single host. LXC does not use virtual machines but creates a virtual environment with its own process space and network stack. All LXC instances share a single instance of the host’s operating system kernel. This system is similar to OpenVZ. Starting with Proxmox VE 4.0, support for OpenVZ was discontinued and completely replaced by LXC.

Useful Tip: While Proxmox relies on LXC for containerization, the principles of creating isolated Linux environments are very similar. If you want to dive deeper into security and learn how to set up a shielded development environment using LXD, we recommend checking out: Gustavo Silva: Setting up a Safe Development Environment in Linux with LXD.

System Requirements

• CPU: 64-bit multi-processor (Intel EMT64 or AMD64), Intel VT/AMD-V support (required for KVM Full Virtualization).
• RAM: 4 GB or more.
• Hardware RAID.
• Storage: Fast hard drives (15k rpm SAS, RAID10).

Storage Note: When planning your disk subsystem on LVM, you will likely need to extend partitions without stopping your virtual machines. For a step-by-step guide on how to handle this, see our article:How to increase the size of the disk if LVM on Proxmox VE.

• Network Card

Minimum Hardware (for testing Proxmox only):

• 64-bit CPU (Intel EMT64 or AMD64).
• CPU/Mainboard with Intel VT/AMD-V support.
• Minimum 1 GB RAM.
• Hard drive.
• One network card.

Important Note on Security and Stability: If you require a production-grade Proxmox installation with guaranteed uptime or fine-tuning for high-load clusters, we recommend consulting professionals. Check out the review and setup services by AMHG —the team not only provides high-performance servers optimized for PVE but also offers professional, turnkey Proxmox configuration. This will save you dozens of hours on network and disk debugging.

Installation and Configuration of Proxmox VE

We will be installing Proxmox VE 8 on Debian 12 (Bookworm), after first verifying that this configuration is listed under supported Proxmox VE versions.

The dedicated server used for this installation has the following specifications:

• CPU: AMD Ryzen 7 7700 Octa-Core “Raphael” (Zen4)
• RAM: 64 GB DDR5
• Storage: 2 x 1 TB NVMe SSD (Gen4, Software-RAID 1)

We will use the official Install Proxmox VE on Debian 12 Bookworm documentation as our guide. First, let’s add the official PVE repository (no-subscription version) and the keys:

echo "deb [arch=amd64] http://download.proxmox.com/debian/pve bookworm pve-no-subscription" > /etc/apt/sources.list.d/pve-install-repo.list
 
wget https://enterprise.proxmox.com/debian/proxmox-release-bookworm.gpg -O /etc/apt/trusted.gpg.d/proxmox-release-bookworm.gpg 

Let’s update the system packages

apt update && apt full-upgrade

Install the Proxmox VE kernel. First, you need to install and boot the Proxmox VE kernel, as some packages depend on specific kernel compilation flags that must be set, or on the presence of feature extensions (such as those for AppArmor).

apt install proxmox-default-kernel
systemctl reboot

Expert tip: After rebooting, check the kernel version. In 2026, you should see something like:

uname -a
Linux proxmox 6.8.x-x-pve #1 SMP PREEMPT_DYNAMIC ...

Let’s install the dependencies: the developers and major packages recommend using `chrony` as a replacement for `systemd-timesyncd`

apt install postfix open-iscsi chrony proxmox-ve -y

Note: Using chrony instead of systemd-timesyncd is critical for cluster stability.

Let’s remove old kernels and packages that Proxmox developers recommend removing

apt remove linux-image-amd64 'linux-image-6.1*'
update-grub
apt remove os-prober

That’s it! Next, log in to the Proxmox web interface https://your-ip-address:8006

Network Configuration: Moving to SDN

The standard vmbr0 bridge is still relevant, but with version 8.x, Proxmox has introduced SDN (Software Defined Networking). You can now create virtual zones (VNETs) directly via the web interface without having to manually edit /etc/network/interfaces.

Expert Tip: When configuring the network, make sure to install the ifupdown2 package. This allows you to apply network changes through the Proxmox GUI without needing to reboot the entire server.

Configuring a Proxmox Network Bridge (vmbr0) on Debian

At the core of all Proxmox virtual networking lies the Linux Bridge (vmbr); you can create up to 4,095 such devices. A network bridge can include both physical and virtual adapters, acting as an unmanaged switch. A physical network card attached to the bridge does not have its own IP settings; instead, it serves as the physical Ethernet interface for that virtual switch. All network configurations are performed within the virtual machines, which gain transparent access to the external network through the bridge and the physical adapter.

What Proxmox Backup Server is Used For

Proxmox Backup Server is an enterprise-class backup and recovery solution based on data deduplication. Below are the core functions of Proxmox Backup Server:

1. VM and Container Backup: Allows for the backup of virtual machines (VMs) and containers running on Proxmox VE or other platforms, supporting both full and incremental backups.
2. Data Deduplication: The system uses deduplication to reduce the required storage footprint by eliminating redundant data across backups.
3. Data Compression and Encryption: Backups can be compressed and encrypted to ensure both storage efficiency and data security.
4. Data Recovery: Provides robust recovery options, including granular file-level restore or full virtual machine recovery.
5. Remote and Local Storage: Supports storing backups both locally and on remote servers (off-site).
6. Task Scheduler: Enables automation of the backup process by setting up custom execution schedules.
7. Management Interface: Features a web-based GUI for managing backup tasks, configuration, and monitoring.
8. Support for Various Storage Types: Compatible with a wide range of storage solutions, including NAS (Network Attached Storage), SAN (Storage Area Networks), and cloud storage.
9. Logging and Monitoring: Provides advanced logging and monitoring features to track backup and restoration processes.
10. API Support: Offers a comprehensive API for integration with third-party systems and task automation.

These features make Proxmox Backup Server a powerful tool for ensuring data reliability and availability in virtualized environments.

Capabilities of Proxmox Mail Gateway

Proxmox Mail Gateway is a comprehensive solution for protecting email infrastructure. It is designed to function as a mail proxy, providing filtering and management of email traffic. Key functions include:

1. Spam Filtering: Uses multiple mechanisms, including spam filter lists, to effectively block unwanted mail (spam).
2. Virus Protection: Integrated antivirus scanners provide protection against viruses and other malware transmitted via email.
3. Content Filtering: Offers the ability to filter message content based on keywords, headers, attachment types, and other criteria.
4. Quarantine: Suspicious or potentially dangerous messages can be automatically quarantined for further analysis.
5. Logging and Reporting: Provides detailed logs and reports on mail traffic, helping administrators track and analyze filtering efficiency.
6. Message Routing: Can be configured to redirect, block, or change the route of emails based on specific rules.
7. Policy Management: Allows for the configuration of email processing policies at the organization, group, or individual user level.
8. Infrastructure Integration: Can be seamlessly integrated into existing mail server setups without requiring significant architectural changes.
9. Web Management Interface: Offers a user-friendly web interface for managing settings, policies, and traffic monitoring.
10. Scalability and Fault Tolerance: Supports high availability (HA) and scalability to ensure the reliable operation of email services.

Proxmox Mail Gateway is a powerful tool for enterprises and organizations looking to protect their mail infrastructure from external threats, improve traffic management, and enhance overall corporate email security.

The Proxmox Ecosystem: PBS and Mail Gateway

1. Proxmox Backup Server (PBS): In 2026, client-side deduplicated incremental backup is the industry standard. Using PBS is essential for ensuring your data is fully protected.
2. Proxmox Mail Gateway: The ideal solution for spam filtering in front of your mail server. Recent versions have introduced enhanced integration with AI-based filtering rules.