The server quit without updating PID file - Ubuntu 12.04 Server

Question

I following this link to upgrade my mysql, https://rtcamp.com/tutorials/mysql/mysql-5-6-ubuntu-12-04/

The article ubuntu is x64, But my ubuntu is x32, So I change the download link to http://cdn.mysql.com/Downloads/MySQL-5.6/mysql-5.6.16-debian6.0-i686.deb

When I finish install, When I type this following command to start mysql: $ service mysql.server start

It alert me :

Starting MySQL
. * The server quit without updating PID file (/var/run/mysqld/mysqld.pid).

When I try to type service mysql-server restart, It alert me a little deferent :

 * MySQL server PID file could not be found!
Starting MySQL
. * The server quit without updating PID file (/var/run/mysqld/mysqld.pid).

There is something maybe help:

• my.cnf is location at /etc/mysql/my.cnf
• ps aux | grep mysql will show different PID when type ps aux | grep mysql again

my.cnf file has the following line

# This will be passed to all mysql clients
# It has been reported that passwords should be enclosed with ticks/quotes
# escpecially if they contain "#" chars...
# Remember to edit /etc/mysql/debian.cnf when changing the socket location.
[client]
port        = 3306
socket      = /var/run/mysqld/mysqld.sock

# Here is entries for some specific programs
# The following values assume you have at least 32M ram

# This was formally known as [safe_mysqld]. Both versions are currently parsed.
[mysqld_safe]
socket      = /var/run/mysqld/mysqld.sock
nice        = 0

Answer 1

Create a new file inside the folder "/var/run/mysqld/" called "mysqld.pid" then edit that file, set line 1 to: 1329 for example then start the server again

Answer 2

Delete all existing pid file by command rm -f 'filename.pid'

And then start the server..

Thanks