Here is a short list of things you might want to run through as you are installing a proxmox server.

• Make sure you’ve downloaded the latest version of Proxmox.
• Have a copy of, or a direct link to, any of the VM ISOs you know you are about to install.
• Add all the hard drives you anticipate using before the install, it’s a bit easier than adding them later.
• Install
• Enable updates: Check Package Repositories - Proxmox VE for details
  • go to /etc/apt/sources.list
  • ensure security updates are always enabled
  • you can disable enterprise update if you don’t have a subscription
  • unstable updates are actually pretty good, but don’t use for production systems. From the above link, the current lines are:

    # PVE pve-no-subscription repository provided by proxmox.com,
    # NOT recommended for production use
    deb http://download.proxmox.com/debian/pve bullseye pve-no-subscription
    

• If you don’t have a proxmox subscription, also comment out the line in /etc/apt/sources.list.d/pve-enterprise.list
• You can then apt-get update and apt dist-upgrade to ensure you’ve got the latest updates. If you added the unstable source, you’ll probably have updates, even if you just installed the latest version of Proxmox.
• If available, ensure IOMMU (or VT-d for intel) is enabled in your BIOS. Especially if you want GPU passthrough.
• Update the /etc/default/grub file:

  #GRUB_CMDLINE_LINUX_DEFAULT="quiet"
  #GRUB_CMDLINE_LINUX_DEFAULT="quiet intel_iommu=on"
  GRUB_CMDLINE_LINUX_DEFAULT="quiet amd_iommu=on"
  

  After editing this file, run update-grub

• then add VFIO modules by editing /etc/modules. Add

  vfio
  vfio_iommu_type1
  vfei_pci
  vfio_virqfd
  

• On the GUI, under Datacenter/Storage remove the local-lvm drive. Then, in the shell:

  lvremove /dev/pve/data
  lvresice -l +100%FREE /dev/pve/root
  resize2fs /dev/mapper/pve-root
  

• On the GUI, Datacenter/Storage -> local. Edit this and ensure that all content types are selected.
• Disable the subscription nag: edit the /usr/share/javascript/proxmox-widget-toolkit/proxmoxlib.js file and find the text “no valid subscription”. Prepend void{( // to Ext.Msg.show
• Install glances for killing VMs that don’t have the Qemu agent installed.
• Run dpkg-reconfigure locales to fix nag messages when using the command line.

Post VM Installation Checklist

• Ensure you can ssh into your VM. (This means both configuring SSH to be available, and installing ssh keys).
• Run your standard post-installation scripts/ ansible playbooks.
• Check best practices for your installed OS.

Adding Qemu-Guest-Agent to a *nix VM

To get extra, useful information on Promox, you should ensure that your VM OS has the qemu-guest-agent tools installed and running.

Step 1: Log in using SSH

You must be logged in via SSH as sudo or root user. Please read this article for instructions if you don’t know how to connect.

Step 2: Install qemu guest agent

$ apt update && apt -y install qemu-guest-agent

Step 3: Enable and Start Qemu Agent

$ systemctl enable qemu-guest-agent
$ systemctl start qemu-guest-agent

Step 4: Verify

Verify that the Qemu quest agent is running

$ systemctl status qemu-guest-agent

Probably also add open-vm-tools on Proxmox and open-vm-tools-desktop on your VM.