How to know if a machine is an Google Compute Engine instance

Question

Is there a way to know from a command line shell if I am currently on a Google Compute Engine machine or somewhere else (development machine)?

Answer 1

You can also do a DNS lookup for the Metadata server, instead of actually calling it.

For example, doing dig +short metadata.google.internal inside a Google Compute instance would output something like this:

[root@vm-1]# dig +short metadata.google.internal
169.254.169.254

If, however, you do the same command (dig +short metadata.google.internal) inside a standard server, outside of Google Cloud, you could get an empty response.

So to check, all you need to do (in bash for instance) is:

GMETADATA_ADDR=`dig +short metadata.google.internal`
if [[ "${GMETADATA_ADDR}" == "" ]]; then
    echo "I am NOT in a Google VM!"
else
    echo "I AM INSIDE a Google VM! Whoohoo!"
fi