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Lab 4.3. Install Docker Engine -

I ran into an issue in lab 4.3 and wanted to share it. The commands to add the Docker GPG key and a stable repository led to the apt command throwing the errors below.

After researching this error, I found the updated commands work without issue.


  • It worked for me when I type a space between "arch=amd64" & "signed-by"

  • Hi @rcrook89,

    Following the correct syntax is critical for commands. Please keep an eye on possible typos that may accidentally end up in commands and instructions typed in the CLI.


  • @chrispokorni It is mostly because "space"s between lines disapear when trying to copy-paste the command from lab pdf to the terminal.


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