http://us.archive.ubuntu.com/ubuntu/dists/trusty-updates/Release
--2016-04-05 14:51:27-- http://us.archive.ubuntu.com/ubuntu/dists/trusty-updates/Release
Resolving us.archive.ubuntu.com (us.archive.ubuntu.com)... 2001:67c:1562::14, 2001:67c:1562::15, 91.189.91.15, ...
Connecting to us.archive.ubuntu.com (us.archive.ubuntu.com)|2001:67c:1562::14|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 64894 (63K)
Saving to: ‘Release’
Release 100%[===============================================================================>] 63.37K 70.7KB/s in 0.9s
2016-04-05 14:51:33 (70.7 KB/s) - ‘Release’ saved [64894/64894]
tj@hephaestion:/tmp/apt$ wget http://us.archive.ubuntu.com/ubuntu/dists/trusty-updates/Release.gpg
--2016-04-05 14:51:36-- http://us.archive.ubuntu.com/ubuntu/dists/trusty-updates/Release.gpg
Resolving us.archive.ubuntu.com (us.archive.ubuntu.com)... 2001:67c:1562::15, 2001:67c:1562::14, 91.189.91.14, ...
Connecting to us.archive.ubuntu.com (us.archive.ubuntu.com)|2001:67c:1562::15|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 933
Saving to: ‘Release.gpg’
Release.gpg 100%[===============================================================================>] 933 --.-KB/s in 0s
2016-04-05 14:51:38 (6.58 MB/s) - ‘Release.gpg’ saved [933/933]
tj@hephaestion:/tmp/apt$ gpg -keyfile /etc/apt/trusted.gpg -verify Release.gpg
gpg: conflicting commands
tj@hephaestion:/tmp/apt$ gpg -keyfile /etc/apt/trusted.gpg -verify Release
gpg: conflicting commands
tj@hephaestion:/tmp/apt$ gpg -keyring /etc/apt/trusted.gpg -verify Release
gpg: conflicting commands
tj@hephaestion:/tmp/apt$ man gpgp
No manual entry for gpgp
tj@hephaestion:/tmp/apt$ man gpg
tj@hephaestion:/tmp/apt$ gpg --keyring /etc/apt/trusted.gpg --verify Release
gpg: no valid OpenPGP data found.
gpg: the signature could not be verified.
Please remember that the signature file (.sig or .asc)
should be the first file given on the command line.
tj@hephaestion:/tmp/apt$ gpg --keyring /etc/apt/trusted.gpg --verify Release.gpg
gpg: no signed data
gpg: can't hash datafile: file open error
tj@hephaestion:/tmp/apt$ gpg --keyring /etc/apt/trusted.gpg --verify Release.gpg Release
gpg: Signature made Tue 05 Apr 2016 09:20:04 BST using DSA key ID 437D05B5
gpg: BAD signature from "Ubuntu Archive Automatic Signing Key <ftpmaster@ubuntu.com>"
gpg: Signature made Tue 05 Apr 2016 09:20:04 BST using RSA key ID C0B21F32
gpg: BAD signature from "Ubuntu Archive Automatic Signing Key (2012) <ftpmaster@ubuntu.com>"