Mysql – Problem to connect to MySQL server (error #2002) in PHP

You are missing the protocol parameter:

mysql --protocol=tcp -u mySqlUser -p mySqlPw

or

mysql -u mySqlUser -p mySqlPw -h localhost --protocol=tcp -P 3306

Both should be the same (localhosst:3306 are default values)

I finally solved the issue in what seems like a ridiculously simple way. I've seen so many posts regarding this problem but the only solution I found that worked was one that was somewhat hidden in a stackoverflow post. It turns out the issue can be solved at connect time (which makes sense):

mysql_connect(HOST,USER,PASS,false,128);

The answer is right there on the manual page, it turns out.

The only thing I still don't understand is why this is necessary on my new Ubuntu install but has never been a problem on any other system, Ubuntu or CentOS.

I should also add that the above method is probably more portable than other methods, since you are setting the connection type in the code rather than in a config file.