It's been over a year since this article was last updated. The information below might be outdated.
If you’ve noticed
apt moaning about a missing GPG key this weekend, you can throw Google your aggrieved glances.
The public signing key that Google issues to sign and authenticate packages distributed through its Linux repositories has changed, resulting in users, perhaps yourself included, seeing various errors thrown up by the package manager.
If you’ve run an
apt update since August 4 you may have seen this error:
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: dl.google.com/linux/chrome/d… stable Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 6494C6D6997C215E
W: Failed to fetch dl.google.com/linux/chrome/d… The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 6494C6D6997C215E
W: Some index files failed to download. They have been ignored, or old ones used instead.
Google signs its packages with GPG keys so that you (and your package manager) can “verify product updates”. When a GPG expires, changes, or is otherwise missing from your system your package manager will display an error, which is precisely what the monospaced gunk above is.
The good news is that it’s easy fix the missing Google GPG key error on Ubuntu: just pop open a new Terminal window and run:
wget -q -O - https://dl.google.com/linux/linux_signing_key.pub | sudo apt-key add -
You’ll be prompted to enter your password (do) and then, well, that’s it. No more ‘failed to fetch’ error on Ubuntu when you run an apt update.
Thanks Oer H.