I have a Debian 9.3 OS on my computer. I have downloaded Ubuntu 18.04 LTS ISO image, which I want to run as a "live CD". However, before I burn it, I would like to verify it.
I try to follow directions on verification given by this tutorial.
When I come to step #4, Retrieve the correct signature key, and run
gpg --verify SHA256SUMS.gpg SHA256SUMS
in the terminal, I get:
gpg: can't open 'SHA256SUMS.gpg': No such file or directory gpg: verify signatures failed: No such file or directory
According to the instructions provided, I should have gotten an error message with some keys, such as:
gpg: Signature made Thu Apr 5 22:19:36 2018 EDT using DSA key ID FBB75451 gpg: Can't check signature: No public key gpg: Signature made Thu Apr 5 22:19:36 2018 EDT using RSA key ID EFE21092 gpg: Can't check signature: No public key
But I don't get this. So, I don't know how to proceed with verification.