How to import OpenPGP key given the key ID in GnuPG?

Question

I'm having a heck of a time installing a Debian Chroot for PPC64. The problem is not debootstrap, rather, its getting GnuPG to locate and install the key I need.

The man pages for gpg are fairly useless, but that's no surprise. Searching is equally frustrating, which is leading me to believe I can't perform the simple task because GnuPG does not support it (it would not be the first time).

Here's what I have tried:

# gpg --version
gpg (GnuPG) 1.4.19
# gpg --import 75DDC3C4A499F1A18CB5F3C8CBF8D6FD518E17E1
gpg: can't open `75DDC3C4A499F1A18CB5F3C8CBF8D6FD518E17E1': No such file or directory
gpg: Total number processed: 0
# gpg --import --key 75DDC3C4A499F1A18CB5F3C8CBF8D6FD518E17E1
gpg: Option "--key" is ambiguous
# gpg --import --keyid 75DDC3C4A499F1A18CB5F3C8CBF8D6FD518E17E1
gpg: unknown keyid-format `75DDC3C4A499F1A18CB5F3C8CBF8D6FD518E17E1'

How do I instruct GnuPG to fetch and install a key based on the key ID?

Answer 1

You are using the wrong option.

--import is used if you want to import the key from a file.

--recv-keys will fetch your keys from a keyserver.

Answer 2

You might actually be suffering from two issues at the same time.

Importing Keys

gpg --import [file] loads key information from a file or stdin, but does not query key servers for the key. gpg --recv-keys does some additional things: it queries a key server (preconfigured in ~/.gnupg/gpg.conf or passed with --keyserver), fetches the result (internally, these two steps are usually implemented as an HTTP request) and finally imports the key.

apt-key

I'm also not sure whether you need that key in your personal GnuPG home directory, or whether you want to install software from third party repositories using apt-get. In this case, don't directly run something like

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv [key-id]

to store the key into apt's "private" keyring (apt-key is a kind of wrapper around GnuPG, for example taking care of storing into the correct keyring). apt does not query your normal user's GnuPG keyring!