Skip to main content

Fixing Network Issues after Cloning (Removing UDEV Rules)

When you clone a snapshot to a new VPS, the hardware remains identical except for one thing: The Network Card (NIC) MAC Address.

Some (older) Linux distributions "remember" the MAC address of the original server in a persistent rule file. When the new server boots, it sees a new MAC address, assumes it is a second network card (e.g., eth1), and fails to apply the network configuration intended for eth0.

The Solution

To fix this, you must delete the rule file so the operating system re-detects the network card upon the next reboot.

Note for Modern Systems:
This issue primarily affects legacy distributions (like CentOS 6 or Ubuntu 14.04). Modern systems (using Netplan or NetworkManager) handle MAC address changes automatically.
If the file mentioned below does not exist, your network issue lies elsewhere (check your interface configuration).

Step-by-step Guide

  1. Access the server via the Video Display console in the dashboard (since SSH likely won't work without a network).

  2. Check if the persistent rules file exists:

    ls /etc/udev/rules.d/70-persistent-net.rules

  3. If the file exists, remove it:

    rm /etc/udev/rules.d/70-persistent-net.rules

  4. Reboot the server immediately:

    reboot

Upon reboot, Linux will generate a fresh rule for the new network card, mapping it correctly to eth0, and your DHCP lease should be acquired successfully.