Proxmox VE on Margrop Blog

Proxmox VE 9.0 Daily Maintenance: Remove the No-Subscription Notice and Use China Mirrors (Updated 2025-08-06)

Sun, 26 Feb 2023 20:00:19 +0800

This article collects the most common maintenance tasks for PVE 6.x / 7.x / 8.x / 9.x and fixes duplicated sections and obvious errors from older revisions.

Check the current version first, then follow the instructions that match that version. Do not mix repository settings across different PVE releases.

pveversion

Stop Clicking Through VMs: A Hands-On Guide to Connecting Proxmox VE to an AI Agent Safely

Sat, 11 Jul 2026 02:30:00 +0800

Connecting an AI agent to Proxmox VE sounds like giving a robot administrator the keys to your datacenter. That is exactly what you should not do. The safe starting point is a dedicated, revocable, read-only API token, a locally running MCP server, and a clear approval boundary for every write operation. This guide explains the architecture, shows manual and agent-assisted setup, and provides one-click installers for Windows 11, Ubuntu 26.

Avoiding the Trap: Why Fail2Ban Fails on Ubuntu 26.04 & PVE 9.2 (And How to Fix It)

Tue, 26 May 2026 22:20:00 +0800

The Bottom Line

With the releases of Ubuntu 26.04 LTS and Proxmox VE (PVE) 9.2, many system administrators, DevOps engineers, and self-hosting enthusiasts have eagerly upgraded or clean-installed these latest systems. However, during the post-installation security hardening phase, you may encounter a highly frustrating scenario: simply copying over your legacy Fail2Ban configuration files from older versions (such as Ubuntu 20.04/22.04 or PVE 7.x/8.x) will either cause the Fail2Ban service to crash during startup or, worse, run silently in the background while completely failing to block external brute-force attacks!

This issue is not caused by a bug in Fail2Ban itself. Instead, it is the result of three “invisible bombs” hidden beneath the surface of these modern Linux distributions, namely changes in the logging architecture, service activation mechanisms, and firewall backends. This article provides an in-depth analysis of these three architectural shifts and introduces a modern, bulletproof Fail2Ban configuration guide fully integrated with systemd-journald and nftables.

Resize the disk of an Ubuntu VM in PVE — the complete workflow from Web UI to guest OS

Mon, 23 Mar 2026 10:30:00 +0800

Preface When you manage a virtualized environment with Proxmox VE, running out of disk space is only a matter of time. Maybe your Ubuntu VM keeps pulling more Docker images, or maybe database logs fill up the root partition. In short, disk expansion is a must-have skill for PVE operations. This article walks through the entire process, from resizing the virtual disk in the PVE Web UI to expanding LVM inside the Ubuntu guest, step by step.

1 Why do we need to resize?

PVE usually allocates a fixed-size virtual disk when a VM is created, for example 32 GB. As the workload grows, that space may no longer be enough. Fortunately, PVE supports online disk expansion, and Ubuntu’s default LVM setup also supports dynamic logical volume expansion. Together, they make the process very convenient.

ProxmoxVE Upgrade from 8 to 9 How to upgrade to PVE9

Wed, 06 Aug 2025 13:28:55 +0800

参考文档：https://pve.proxmox.com/wiki/Upgrade_from_8_to_9 Preparation before upgrading pve8to9 apt update apt dist-upgrade pveversion #reboot 建议更新完毕后重启1次 Operation step one (back up existing files) cp /etc/apt/sources.list /etc/apt/sources.list_202508_bak cp /etc/apt/sources.list.d/pve-install-repo.list /etc/apt/sources.list.d/pve-install-repo.list_202508_bak Operation step two (start upgrading) sed -i 's/bookworm/trixie/g' /etc/apt/sources.list sed -i 's/bookworm/trixie/g' /etc/apt/sources.list.d/pve-install-repo.list apt update apt dist-upgrade Operation step three (remove unsubscribed prompts) sed -i_orig "s/data.status === 'Active'/true/g" /usr/share/pve-manager/js/pvemanagerlib.js sed -i_orig "s/if (res === null || res === undefined || \!res || res/if(/g" /usr/share/javascript/proxmox-widget-toolkit/proxmoxlib.js sed -i_orig "s/.

PVE disk inspection connected to UptimeKuma - the 404 pitfall and the final script

Wed, 14 May 2025 22:16:48 +0800

Read first The previous article showed how to push the PVE host’s LVM-Thin usage to UptimeKuma. After following the instructions, some readers got a 404 when the script used curl. This article explains the cause, fixes the script, and provides an optional upgrade path. Follow along from scratch and you should succeed on the first try. 1 Phenomenon: curl ... 404 curl -fsS --retry 3 \ "${PUSH_URL}?status=up&msg=OK" \ -H 'Content-Type: application/json' \ --data-raw "$result" # ↳ curl: (22) The requested URL returned error: 404 The same URL works in a browser or with curl GET:

PVE host disk space monitoring - from pitfalls to UptimeKuma

Wed, 14 May 2025 22:11:33 +0800

Target Reader This article is written for readers who have just started using Proxmox VE (referred to as PVE) and want to copy the steps and get it running. The article aims to: explain why the problem happens provide the full command at each step give troubleshooting ideas when something goes wrong 0 Background - What went wrong? The official PVE installation wizard defaults to putting the VM disk into the LVM-Thin pool (commonly pve/data)

An Effective Method to Quickly Set Up Fail2ban in Proxmox VE to Prevent Multiple Failed Login Attempts

Tue, 18 Jun 2024 15:33:01 +0800

This briefly introduces how to set up Fail2ban in Proxmox VE to temporarily block IP addresses with multiple failed login attempts.

Install Fail2ban

Execute the following commands as root on the Proxmox VE host:

apt update
apt install fail2ban

Configure Basic Settings

It is recommended to use the /etc/fail2ban/jail.local file, whose settings take precedence over jail.conf. Use the following command to copy the template:

cp /etc/fail2ban/jail.conf /etc/fail2ban/jail.local

N5105 Proxmox VE 8.2 version, solving the problem of frequent virtual machine crashes

Sat, 04 May 2024 07:55:22 +0800

1. Problem background Recently, major PT websites were developed and registered on May Day, so I registered several websites, and then downloaded and uploaded them like crazy in order to complete novice tasks. As soft routers, N5105 and iKuai, when under high load for a long time, the virtual machine crashed randomly, and the CPU remained at 100% for a long time. The virtual machine could only be killed and restarted, which greatly affected the completion of novice tasks.

Installing a Minimal k8s Environment with Minikube

Tue, 30 Apr 2024 19:37:29 +0800

Deploying Minikube on Proxmox VE (a Debian-based virtualization environment) requires consideration of Proxmox’s characteristics, as it is essentially a virtual machine and container management platform. You will need to create a virtual machine (VM) on Proxmox VE and then install Minikube within that VM. Below are the detailed steps:

Upgrade ProxmoxVE 7.4 to 8.0, detailed steps

Sat, 08 Jul 2023 10:25:13 +0800

Step 1: Read the official documentation in detail Notice: If you use ssh connection remotely, it is recommended to use the screen command first to avoid various problems caused by network instability and operation interruption. Step 2: Upgrade to the latest version 7.4 The latest version is 7.4.15 apt update -y && apt dist-upgrade -y sed -i_orig "s/data.status === 'Active'/true/g" /usr/share/pve-manager/js/pvemanagerlib.js sed -i_orig "s/if (res === null || res === undefined || \!

Proxmox VE 6.4 daily upgrade commands

Mon, 29 Mar 2021 08:23:52 +0800

Remove unused Linux kernel pvekclean Update software: apt update -y && apt dist-upgrade -y Remove the unsubscribed prompt and support PVE 6.3 / 6.4 sed -i_orig "s/data.status === 'Active'/true/g" /usr/share/pve-manager/js/pvemanagerlib.js sed -i_orig "s/if (res === null || res === undefined || \!res || res/if(/g" /usr/share/javascript/proxmox-widget-toolkit/proxmoxlib.js sed -i_orig "s/.data.status.toLowerCase() !== 'active'/false/g" /usr/share/javascript/proxmox-widget-toolkit/proxmoxlib.js systemctl restart pveproxy After confirming that everything is correct, restart the server. reboot Solve software upgrade problems Added Alibaba Cloud’s Debian image source

How to Install Jike AC Virtual Machine in Proxmox VE Environment?

Wed, 03 Feb 2021 16:18:33 +0800

According to 恩山的集客AC AP扫盲贴:

Q: Can I skip AC and have two AP connect directly to the main router for roaming? A: Yes, but roaming works better with AC than without it. With ac present, roaming performance won’t disappoint. Jike’s roaming is not a simple weak-signal kick. With ac in place, excellent roaming effects are achieved regardless of whether Jike ap supports kvr, because ac+ap is proactive roaming, which does not rely on kvr protocol and has very low requirements on clients. Micro ac only handles configuration distribution and cannot perform proactive roaming; roaming effectiveness depends on the client.

Let's Encrypt automatically synchronizes Proxmox VE and DSM certificates after automatic renewal

Tue, 02 Feb 2021 19:19:38 +0800

Last time we talked about Let’s Encrypt通过DNS TXT记录来验证域名有效性, and the last part of the article was about how to use certbot renew for automatic renewal. Then the automatic renewal is successful, how to synchronize it to PVE and DSM? Below we use a script to perform automatic synchronization. Need to configure SSH password-free login on Proxmox VE and DSM servers Automatically synchronize Proxmox VE certificate Proxmox VE synchronized to this machine Proxmox VE synchronized to LAN cp /etc/letsencrypt/live/blog.

How to Import a Third-Party VM Image into Proxmox VE

Mon, 01 Feb 2021 15:12:47 +0800

In the example below, the VM ID is always 100; change it as needed.

File Format Conversion

Use qemu-img to convert virtual disk files in other formats to qcow2
For example, the following converts vmdk to qcow2

How to Configure a Freshly Installed Ubuntu 20.04 Server VM on PVE

Sat, 30 Jan 2021 15:33:44 +0800

Download the Installation ISO

Aliyun Ubuntu 20.04 live server download Aliyun Ubuntu 18.04 live server download

Enable Intel GVT-g Graphics Virtualization on Proxmox VE

Sat, 23 Jan 2021 11:23:04 +0800

Note: Intel GVT-g is currently only supported by fifth, sixth, and seventh generation Intel Core processors and Xeon E3 v4/v5/v6 processors on PVE. My tests show that 8th generation and newer CPUs are not supported for now -_-! If this changes, feel free to contact me. Reference: https://pve.proxmox.com/wiki/PCI(e)_Passthrough

Proxmox VE commonly used local paths, and how to modify hosts, host name, IP address and DNS configuration

Fri, 22 Jan 2021 17:02:01 +0800

PVE local ISO file directory: /var/lib/vz/template/iso PVE local OVZ file directory: /var/lib/vz/template/cache Modify hosts file Effective after restart vi /etc/hosts Modify hostname Effective after restart vi /etc/hostname Modify IP address and DNS configuration Effective after restart Reference DNS configuration vi /etc/network/interfaces dns-nameservers 114.114.114.114,223.5.5.5

Initialization script after Proxmox VE installation

Fri, 22 Jan 2021 16:42:46 +0800

In order to facilitate the installation of PVE, I compiled the relevant commands myself. Please modify them according to your own environment.

ProxmoxVE 6.3 uses commands to back up Synology virtual machines

Thu, 21 Jan 2021 18:16:22 +0800

Since the Synology virtual machine in my ProxmoxVE runs on a LUN passthrough disk, I cannot click backup directly in the Web interface. DSM virtual machine backup process: Stop the virtual machine -> Unmount the hard disk -> Back up the virtual machine -> Mount the hard disk -> Start the virtual machine It is really troublesome and error-prone to do this entirely through the Web interface. So I studied the command-line workflow.

Does Synology DSM Support QEMU Guest Agent?

Wed, 20 Jan 2021 13:19:28 +0800

Install the Power Button Package in Synology DSM and disable the qemu agent option in PVE.

Where to Download the Power Button Package

Note that DSM 6.1 and DSM 6.2 use different spk packages

img2KVM, Convert IMG Format to KVM Format, Install DSM Synology Virtual Machine

Wed, 20 Jan 2021 08:32:25 +0800

Install img2kvm

cd /root
wget -c https://download.margrop.net/d/oneindex/network/PVE/img2kvm -O img2kvm
chmod +x img2kvm

Solution to PVE upgrade failure due to insufficient boot space

Sun, 17 Jan 2021 19:25:59 +0800

During the default installation, the space allocated by proxmox to /boot is less than 300M. The iteration of proxmox is very fast, and /boot can easily be filled up. If you are not careful, the upgrade will fail. The only way is to manually delete the old kernel. Delete old kernel proxmox is based on debian. Every time you use apt update && apt dist-upgrade, debian’s linux-image and pve-kernel will be automatically installed.