This document describes common errors that you may run into when using nested virtualization and methods for resolving those errors. For more information about nested virtualization, see Creating nested VMs.
Can't start nested VM
If your project is part of an organization, your organization might have disabled the ability to create VMs with nested virtualization. Make sure that nested virtualization is allowed before you try to create a VM that has nested virtualization enabled.
Processor not displaying nested virtualization
grep -c vmx /proc/cpuinfo command returns
0 and reports that the VM
is not enabled for nesting, make sure that you have started your VM with a CPU
platform of Haswell or later. For more information, see Nested virtualization
Can't exit nested VM
If you did not run
screen before each nested VM session, you can either
shut down the nested VM or stop the process from another terminal. To shut down
the nested VM, run the
poweroff command from within your nested VM.
Alternatively, log into the host VM in another terminal and end the process,
screen on the host VM before you start a new nested VM.
iptables not forwarding traffic
iptablesresolve rules from top to bottom. Make sure your rules are higher priority than other rules.
- Check that there are no conflicting rules intercepting your packets.
Consider flushing your
First, set the default policies:
sudo iptables -P INPUT ACCEPT sudo iptables -P FORWARD ACCEPT sudo iptables -P OUTPUT ACCEPT
Next, flush all tables and chains, and delete non-default chains:
sudo iptables -t nat -F sudo iptables -t mangle -F sudo iptables -F sudo iptables -X