the_information_nexus/tech_docs/virtualization/proxmox_dhcp.md

For your standalone Proxmox setup, switching between static and dynamic IP configurations and managing virtual bridges are important tasks. Below, I'll provide a concise guide to handle these changes effectively and safely.

Switching from Static IP to DHCP:

• Backup Configurations: Always backup configuration files before making changes (cp /etc/network/interfaces /etc/network/interfaces.bak).

cp /etc/network/interfaces /etc/network/interfaces.bak

Update Network Interface Configuration: Open /etc/network/interfaces in a text editor:

vim /etc/network/interfaces

• Change the vmbr0 configuration from static to DHCP:

auto vmbr0
iface vmbr0 inet dhcp
    bridge-ports enp3s0
    bridge-stp off
    bridge-fd 0

• Save the changes and exit the editor.

• Restart Networking to Apply Changes:

• Apply the new network settings:

systemctl restart networking

• Find the New DHCP-Assigned IP Address:
• After the network restarts, check the assigned IP:

ip addr show vmbr0

• Update /etc/hosts with the New IP:
• Edit the /etc/hosts file to replace the old static IP with the new one:

nano /etc/hosts

• Modify the line with the old IP to the new one you just obtained:

192.168.86.62 whitebox.foxtrot.lan whitebox  # Old IP
192.168.x.x whitebox.foxtrot.lan whitebox    # New DHCP IP

• Save and exit.

Creating a New Virtual Bridge (vmbrX):

• Add a New Virtual Bridge Configuration:

  • Edit /etc/network/interfaces:

    vim /etc/network/interfaces
    

  • Add a new bridge configuration at the end of the file:

    auto vmbrX  # Replace X with the next available number
    iface vmbrX inet manual
        bridge-ports none
        bridge-stp off
        bridge-fd 0
    

  • Save and exit the editor.

• Activate the New Bridge:

  • Restart the networking service to bring up the new bridge:

    systemctl restart networking
    

General Notes: