None of these worked for me:
$ sudo apt-key adv --keyserver hkp://pgp.mit.edu:80 --recv-keys 5072E1F5
$ sudo apt-key adv --keyserver pgp.mit.edu --recv-keys 5072E1F5
$ sudo apt-key adv --keyserver pgp.mit.edu --recv-keys A4A9406876FCBD3C456770C88C718D3B5072E1F5
The sources for those are:
https://bugs.mysql.com/bug.php?id=85029 and https://bugs.mysql.com/bug.php?id=94378
I performed one suspect operation in desperation (saying 'y' instead of 'N' below) which I think wasn't required at all:
$ sudo apt-get install mysql-apt-config
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages will be upgraded:
1 upgraded, 0 newly installed, 0 to remove and 294 not upgraded.
Need to get 35.6 kB of archives.
After this operation, 0 B of additional disk space will be used.
WARNING: The following packages cannot be authenticated!
Install these packages without verification? [y/N] y
Get:1 http://repo.mysql.com/apt/ubuntu/ trusty/mysql-apt-config mysql-apt-config all 0.8.13-1 [35.6 kB]
Fetched 35.6 kB in 0s (229 kB/s)
Preconfiguring packages ...
dpkg-deb: error: archive '/var/cache/apt/archives/mysql-apt-config_0.8.13-1_all.deb' has premature member 'control.tar.xz' before 'contro
l.tar.gz', giving up
dpkg: error processing archive /var/cache/apt/archives/mysql-apt-config_0.8.13-1_all.deb (--unpack):
subprocess dpkg-deb --control returned error exit status 2
Errors were encountered while processing:
E: Sub-process /usr/bin/dpkg returned an error code (1)
And followed it with:
$ sudo apt-get update
which did not help.
I still got the same error.
Finally, the following worked:
$ sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 5072E1F5
I'm speculating (blindly) that maybe pgp.mit.edu has changed their structure or maybe "MySQL Release Engineering" (run
apt-key list) has moved their keys to the ubuntu key server or some such thing (I have no idea of how keys are maintained).
This comment on the duplicate thread says the same thing.
Hope this saves someone some time and effort.