CI 3 won't connect to MSSQL 2012 database under php 5.6 on Rackspace

Our site is on Rackspace cloud sites and is currently running fine with Codeigniter 3.0.0 on PHP 5.4.1.0 and connecting to a MSSQL 2012 database. Rackspace is in the process of upgrading PHP from 5.4.1.0 to 5.6.7-1 and has given testlinks for testing our websites in the new PHP environment. In this test environment, the site does not connect to the MSSQL database. However - no errors are thrown (that I can find, anyway!)

This is what I have for my database configuration:

PHP Code:

$db['default'] = array(
    'dsn'   => '',
    'hostname' => 'mssqlXXXX.XXX',
    'username' => 'USERNAME',
    'password' => 'PASSWORD',
    'database' => 'DATABASE NAME',
    'dbdriver' => 'mssql',
    'dbprefix' => '',
    'pconnect' => FALSE,
    'db_debug' => TRUE,
    'cache_on' => FALSE,
    'cachedir' => '',
    'char_set' => 'utf8',
    'dbcollat' => 'utf8_general_ci',
    'swap_pre' => '',
    'encrypt' => FALSE,
    'compress' => FALSE,
    'stricton' => FALSE,
    'failover' => array(),
    'save_queries' => TRUE
); 


As a test, Rackspace also had me write a test controller. This works in Codeigniter:

PHP Code:

$username = "USERNAME";
$password = "PASSWORD";
$hostname = 'mssqlXXXX.XXX';
$dbname = "DATABASE";

//connection to the database
$dbcon = mssql_connect($hostname, $username, $password)or die("Unable to connect to MSSQL");
echo "Connected to MSSQL";

//select the database
mssql_select_db($dbname, $dbcon);

//SQL Select statement
$sqlselect = "SELECT * FROM INFORMATION_SCHEMA.TABLES";

//Run the SQL query
$sqlquery = mssql_query($sqlselect);

//Output the query results
while ($result = mssql_fetch_array($sqlquery) )
{
    echo "<br>";
    print_r($result);
    echo "<br>";
} 


Any clues why the standard Codigniter database connection is not working?

It turns out that this was a Rackspace issue and it has been corrected. Problem solved.