I found this error on a fresh install of the Docker container provided by Mgt Development Environment:
root@mgt-dev-70:~# /etc/init.d/mysql start
/usr/sbin/mysqld: error while loading shared libraries: libpthread.so.0: cannot open shared object file: Permission denied
[....] Starting MySQL (Percona Server) database server: mysqld/usr/sbin/mysqld: error while loading shared libraries: libpthread.so.0: cannot open shared object file: Permission denied
/usr/sbin/mysqld: error while loading shared libraries: libpthread.so.0: cannot open shared object file: Permission denied
./usr/sbin/mysqld: error while loading shared libraries: libpthread.so.0: cannot open shared object file: Permission denied
./usr/sbin/mysqld: error while loading shared libraries: libpthread.so.0: cannot open shared object file: Permission denied
I used this tutorial https://www.mgt-commerce.com/documentation/mgt-development-environment-run-container and I pulled mgtcommerce/mgt-development-environment-7.0
As we see it is a problem with apparmor.
You can fix it by log in the container and run the commands below.