After I installed the docker, when I try to use the sudo apt update command, I get the following error:
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: focal InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 7EA0A9C34573JCD8 W: Failed to fetch The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 7EA0A9C34573JCD8 W: Some index files failed to download. They have been ignored, or old ones used instead. 2 Answers
It looks like that you haven't added official gpg key of docker repository. Open terminal and execute below command.
curl -fsSL | sudo apt-key add - I edited :
/etc/apt/sources.list
using the vim editor : sudo vim /etc/apt/sources.list And I put a # character at the beginning of the line that included the docker link.
# deb-src [arch=amd64] focal stable1
