Connecting to a remote database through CodeIgniter

问题

Unable to connect to your database server using the provided settings.

I've been having difficulty connecting my application to my remote database. I'm receiving the error shown above when I run my application. I've looked at previous answers to this question on this site, but I've gotten no luck at solving it. From what I learnt, I need to replace the hostname and make my mysql database accept external connections, which I have both done. I tried the same values in my database.php through the mysql command-line and it works.

So what else could I possibly be missing?

Here are my settings in database.php:

$active_group = 'staging';
$active_record = TRUE;

$db['default']['hostname'] = 'localhost';
$db['default']['username'] = 'root';
$db['default']['password'] = '';
$db['default']['database'] = 'myDatabase';
$db['default']['dbdriver'] = 'mysql';
$db['default']['dbprefix'] = '';
$db['default']['pconnect'] = TRUE;
$db['default']['db_debug'] = TRUE;
$db['default']['cache_on'] = FALSE;
$db['default']['cachedir'] = '';
$db['default']['char_set'] = 'utf8';
$db['default']['dbcollat'] = 'utf8_general_ci';
$db['default']['swap_pre'] = '';
$db['default']['autoinit'] = TRUE;
$db['default']['stricton'] = FALSE;

$db['staging']['hostname'] = 'XX.XX.XXX.XXX';
$db['staging']['username'] = 'user';
$db['staging']['password'] = 'pwd';
$db['staging']['database'] = 'myDatabase';
$db['staging']['dbdriver'] = 'mysql';
$db['staging']['dbprefix'] = '';
$db['staging']['pconnect'] = TRUE;
$db['staging']['db_debug'] = TRUE;
$db['staging']['cache_on'] = FALSE;
$db['staging']['cachedir'] = '';
$db['staging']['char_set'] = 'utf8';
$db['staging']['dbcollat'] = 'utf8_general_ci';
$db['staging']['swap_pre'] = '';
$db['staging']['autoinit'] = TRUE;
$db['staging']['stricton'] = FALSE;

回答1:

try this command from your shell to see if you can connect:

mysql -h HOSTNAME -uUSERNAME -p DATABASE

also check to see if you don't have a different port to connect to mysql set, by default codeigniter will connect to 3306, unless you define the actual port set. this might be the issue.

good luck

回答2:

mysql by default accepts only localhost connections, make sure your server is configured properly locally

http://www.cyberciti.biz/tips/how-do-i-enable-remote-access-to-mysql-database-server.html

make sure that your server isn't behind a router that's in a private subnet, you might neet to configure static NAT for portforwarding your server into the web

回答3:

$active_group = 'staging';
$active_record = TRUE;

try to change above code to

$active_group = 'default';
$active_record = TRUE;

回答4:

If you have enforced SELinux Policy in your server make sure you enable httpd_can_network_connect boolean flag

setsebool -P httpd_can_network_connect=1

来源：https://stackoverflow.com/questions/8107449/connecting-to-a-remote-database-through-codeigniter