Could not connect: Lost connection to MySQL server at 'reading initial communication packet', system error: 0

You might want to check your /etc/hosts.deny where:

ALL: ALL: DENY

mysqld: ALL: DENY

is your enemy.

mysql ruby database-connection

Rebooting the server worked for me. No settings changes needed.

mysql ruby database-connection

check from that host

shell> telnet IP 3306

If MySQL is up and reachable you'll see mysql version in telnet output.Otherwise check firewall, etc until telnet succeeds.

Then I advice you first connect with native mysql client to exclude Rails from problem aria.

CodeHunter