Can not authorize into the ispmanager 6 without any error

Symptoms

After entering the login and password and clicking the Login button, the authorization page is refreshed, but the login to the ispmanager panel web interface is not performed. 

Causes

Insufficient free space on the server disk or no free inodes.

Solution

Connect to the server via SSH to check the amount of free disk space and the number of free inodes of the root partition (the / symbol in the «Mounted on» column):

1. Enter the df -h command to check the amount of free disk space;
2. Enter the df -ih command to check the number of free inodes on the disk.

Free disk space can be increased by deleting large or by increasing the total disk capacity.

In the case of inodes, increasing the disk capacity will not increase their total number, since the number is set when the file system is installed. Each inode is linked to a single file, so it is most efficient to delete multiple small files, such as old log files or temporary files.