Ubuntu 20.+ - Machine id reset script

Purpose

Description

In case of cloning Ubuntu OS with version 20.+ we can notice that DHCP treat all virtual machines as one. Possible reason could be that machine id for all OS copies is the same.

To check machine-id use command:

cat /etc/machine-id

Conditions

• Virtualization (Virtualbox, Vmware)
• Cloned Ubuntu Virtual Machines have assigned same IP address by DHCP.
• Machine-Id doesn't change

Solution

Script

1. Enter source Ubuntu VM
2. Download script and make it executable

wget https://raw.githubusercontent.com/greencashew/ubuntu-20-machine-id-reset-script/main/reset-machine-id.sh && chmod +x reset-machine-id.sh

1. Run sudo ./reset-machine-id.sh install
2. Clone source virtual machine
3. Start cloned virtual machines
4. Machine id-s for each VM should be different.

Usage in details

 sudo ./reset-machine-id.sh                 Reset machine id and create already run indicator under path $RESET_FILE_PATH

 sudo ./reset-machine-id.sh install         Install service which run reset-machine-id.sh on every system startup if indicator file $RESET_FILE_PATH doesn't exists.
 sudo ./reset-machine-id.sh prepare         Remove indicator file so reset id script file can run during next startup.
 sudo ./reset-machine-id.sh uninstall       Uninstall script
 sudo ./reset-machine-id.sh help            Open this help

Manual solution

You can also run below commands manually on each machine:

sudo rm -f /etc/machine-id
sudo dbus-uuidgen --ensure=/etc/machine-id
sudo rm /var/lib/dbus/machine-id
sudo dbus-uuidgen --ensure
sudo dhclient -r