Proxmox Notes

Networking #

NAT config #

For my setup, I have one physical Ethernet connection on eno1 device, which by default is assigned to vmbr0.

I configured a NAT bridge vmbr1 by following the instructions from the Proxmox Network config Guide.

The config for vmbr1 is as follows:

auto vmbr1
iface vmbr1 inet static
        address 203.0.113.0/24
        bridge-ports none
        bridge-stp off
        bridge-fd 0
        post-up   echo 1 > /proc/sys/net/ipv4/ip_forward
        post-up   iptables -t nat -A POSTROUTING -s '203.0.113.0/24' -o vmbr0 -j MASQUERADE
        post-down iptables -t nat -D POSTROUTING -s '203.0.113.0/24' -o vmbr0 -j MASQUERADE

After config, restart the networking service:

systemctl restart networking

VLAN config #

I wanted to set up VLAN for testing purposes and found this useful thread on the Proxmox Forum.

The config is similar to the NAT setup but includes VLAN-specific settings:

 auto vmbr1
 iface vmbr1 inet static
         address 203.0.113.0/24
         bridge-ports none
         bridge-stp off
         bridge-fd 0

         post-up   echo 1 > /proc/sys/net/ipv4/ip_forward
-        post-up   iptables -t nat -A POSTROUTING -s '203.0.113.0/24' -o vmbr0 -j MASQUERADE
+        post-up   iptables -t nat -A POSTROUTING -s '203.0.0.0/16' -o vmbr0 -j MASQUERADE
-        post-down iptables -t nat -D POSTROUTING -s '203.0.113.0/24' -o vmbr0 -j MASQUERADE
+        post-down iptables -t nat -D POSTROUTING -s '203.0.0.0/16' -o vmbr0 -j MASQUERADE

+auto vmbr1.114
+iface vmbr1.114 inet static
+    address 203.0.114.1
+    netmask 255.255.255.0

Managing ISO and VM Images #

Uploading ISO #

To upload an ISO file to Proxmox, follow the instructions detailed in the OVHcloud Support: Go to local > Upload > Select File.

Importing ovf #

For setting up GNS3 on Proxmox, I downloaded the GNS3 VM from GNS3 VM Download.

Since GNS3 VM is available only in VMware ESXi (OVF) format, use the following command to import it to Proxmox, as explained in Zach Grace’s Proxmox Cheat Sheet:

qm importovf <vmid> <ovf file> <storage>

Enabling Nested Virtualization #

Nested virtualization can be enabled in Proxmox by referring to the Proxmox Nested Virtualization Guide:

qm set <vmid> --cpu host

Creating VM with Cloud Image and Cloud-Init #

To create a VM using a cloud image and cloud-init, use the steps provided in the Proxmox Cloud-Init Support:

Create as Template

wget https://cloud-images.ubuntu.com/bionic/current/bionic-server-cloudimg-amd64.img
qm create 9000 --memory 2048 --net0 virtio,bridge=vmbr0 --scsihw virtio-scsi-pci
qm set 9000 --scsi0 local-lvm:0,import-from=/path/to/bionic-server-cloudimg-amd64.img
qm set 9000 --ide2 local-lvm:cloudinit
qm set 9000 --boot order=scsi0
qm set 9000 --serial0 socket --vga serial0
qm template 9000

Create VM

qm clone 9000 123 --name ubuntu2
qm set 123 --sshkey ~/.ssh/id_rsa.pub
qm set 123 --ipconfig0 ip=10.0.10.123/24,gw=10.0.10.1

Updating Proxmox Without Subscription #

The default repository requires a paid subscription for Proxmox updates.

However, it’s possible to bypass this by manually changing the repository settings, as outlined in the VirtualizationHowTo Guide.

vim /etc/apt/sources.list.d/pve-enterprise.list

-deb https://enterprise.proxmox.com/debian/pve bookworm enterprise
+deb http://download.proxmox.com/debian/pve bookworm pve-no-subscription

vim /etc/apt/sources.list.d/ceph.list

-deb https://enterprise.proxmox.com/debian/ceph-quincy bookworm enterprise
+deb http://download.proxmox.com/debian/ceph-quincy bookworm no-subscription