No space left on device in server | PHPMysql not connect session | Full Inodes 100% | Check CPU Process and MEMORY

Issues

1. open(/var/lib/php/sessions/sess_, O_RDWR) failed: No space left on device (28)
2. PHPMysql not connect
3. Database not connect

Solusions

Check CPU and MEMORY usage of server from terminal

ps -eo pid,ppid,cmd,%mem,%cpu --sort=-%cpu | head

df -h

Check file size

find /home/ -size +100M 

 

 Check INODES in server (Inode mean total files into server)

df -i

Search INODES from system and perticular folder (Get number of file in perticular directory)

for i in /var/www/html/*; do echo $i; find $i |wc -l; done

Check INODES into specific directory

ls -l /var/lib/php/sessions | wc -l

Remove all files from specific directory

rm -r /var/lib/php/sessions/ 

If you are using PHP so you can create code in any existing file

$path = '/var/lib/php/sessions/';
$dir = opendir($path);
$i = 0;
while ($dir && ($file = readdir($dir)) !== false) {
    unlink($path.$file);
    echo $i.' - '.$path.$file.'<br>';
    if($i == 50000){
        exit;
    }
    $i++;
}

How to Set, Retrieve and Unset Session Variables in Magento

Set session Data

$session = Mage::getSingleton("core/session", array("name"=>"frontend"));

$session->setData("day_filter", 'weeks');
$session->setData("days", '5');          
$session->setData("next_delivery_date", '2012-05-12');

or

Mage::getSingleton('core/session')->setIsSalesrepTax('test'); 

UnSet session Data

$session->unsetData('day_filter');
$session->unsetData('days');
$session->unsetData('next_delivery_date'); 

$session->unsetData('IsSalesrepTax');  

Session Data Set to null

$session->setData('day_filter', NULL);
$session->setData('days', NULL);
$session->setData('next_delivery_date', NULL); 

Magento Set, Retrieve and Unset Session Variables

 To set a Magento session variable:

$myValue = 'My session';
Mage::getSingleton('core/session')->setMyValue($myValue);

To Retrieve:

$myValue=Mage::getSingleton('core/session')->getMyValue();

To Unset:

Mage::getSingleton('core/session')->unsMyValue();