Additional uncaught exception thrown while handling exception.

Original

PDOException: SQLSTATE[HY000] [2003] Can't connect to MySQL server on 'mysql' (111) in _registry_check_code() (line 3154 of /srv/www/drupal7sites/public_html/includes/bootstrap.inc).

Additional

PDOException: SQLSTATE[HY000] [2003] Can't connect to MySQL server on 'mysql' (111) in _registry_check_code() (line 3154 of /srv/www/drupal7sites/public_html/includes/bootstrap.inc).