Sorry, this is a bit lazy of me, but at the moment I can only confirm that this works on Ubuntu 10.04.4 LTS. It might, however, work on other versions too, and maybe also with Debian of course.
If when you run an apt-get update you are being told something like this right at the end:
W: GPG error: http://196.x.y.z lucid Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 2940ABA983EF826A
… then install “add-apt-key” on the box, and run it, adding the missing key itself to the end of the command, as shown below.
root@xyz-box-bry-01:~# apt-get install add-apt-key Reading package lists... Done Building dependency tree Reading state information... Done The following NEW packages will be installed: add-apt-key 0 upgraded, 1 newly installed, 0 to remove and 5 not upgraded. Need to get 5,314B of archives. After this operation, 81.9kB of additional disk space will be used. Get:1 http://196.x.y.z/ubuntu/ lucid/universe add-apt-key 1.0-0.5 [5,314B] Fetched 5,314B in 0s (270kB/s) Selecting previously deselected package add-apt-key. (Reading database ... 88896 files and directories currently installed.) Unpacking add-apt-key (from .../add-apt-key_1.0-0.5_all.deb) ... Processing triggers for man-db ... Setting up add-apt-key (1.0-0.5) ... root@xyz-box-bry-01:~# add-apt-key 2940ABA983EF826A gpg: directory `/root/.gnupg' created gpg: new configuration file `/root/.gnupg/gpg.conf' created gpg: WARNING: options in `/root/.gnupg/gpg.conf' are not yet active during this run gpg: keyring `/root/.gnupg/secring.gpg' created gpg: keyring `/root/.gnupg/pubring.gpg' created gpg: requesting key 83EF826A from hkp server subkeys.pgp.net gpg: /root/.gnupg/trustdb.gpg: trustdb created gpg: key 83EF826A: public key "Opscode Packages " imported gpg: Total number processed: 1 gpg: imported: 1 OK root@xyz-box-bry-01:~#
I’ve found that sometimes the key server doesn’t have the key and so it’s not imported, but re-running the command generally fixes that as the next key server chosen usually does end up having the key. Once you’ve successfully imported the key, run “apt-get update” again and your problem should no longer exist.
There was something else I wanted to say but I’ve totally forgotten what it was.