Resolved - open_basedir restriction in effect. File(/var/lib/php/session) is not within the allowed path(s): (/var/www/vhosts/mydomain.com/:/tmp/)

While uploading the Codeigniter project to Plesk hosting, we will get this type of error open_basedir restriction in effect because in Plesk hosting there is no default tmp folder as compared to other hosting like Cpanel of HostGator, GoDaddy, Hostinger, etc, Other hosting has their own default tmp folder.

So, to fix this issue, we need to do two things,

1. First of all, create a tmp folder at the Home directory of Plesk file manager.
2. On the config file, we have to configure the tmp folder in the variable $config['sess_save_path'] just add the value of /tmp.