gistfile1.txt

ubuntu@ip-10-107-20-19:~$ sudo mysql_install_db --basedir=/usr --defaults-extra-file=/etc/mysql/my.cnf --datadir=/mnt/tmpfs/mysql --user=mysql
Installing MySQL system tables...
150518 13:17:15 [Note] /usr/sbin/mysqld (mysqld 5.5.43-0ubuntu0.14.04.1) starting as process 10551 ...
150518 13:17:15 [Warning] Can't create test file /mnt/tmpfs/mysql/ip-10-107-20-19.lower-test
150518 13:17:15 [Warning] Can't create test file /mnt/tmpfs/mysql/ip-10-107-20-19.lower-test

Installation of system tables failed!  Examine the logs in
/mnt/tmpfs/mysql for more information.

You can try to start the mysqld daemon with:

    shell> /usr/sbin/mysqld --skip-grant &

and use the command line tool /usr/bin/mysql
to connect to the mysql database and look at the grant tables:

    shell> /usr/bin/mysql -u root mysql
    mysql> show tables

Try 'mysqld --help' if you have problems with paths.  Using --log
gives you a log in /mnt/tmpfs/mysql that may be helpful.

Please consult the MySQL manual section
'Problems running mysql_install_db', and the manual section that
describes problems on your OS.  Another information source are the
MySQL email archives available at http://lists.mysql.com/.

Please check all of the above before submitting a bug report
at http://bugs.mysql.com/