Ever seen a 404 error? This is what it looks like.

500 Internal Server Error

PHP Request Shutdown: Write failed: No space left on device (28) (2)

#0 [internal function]: flight\Engine->handleError()
#1 {main}

500 Internal Server Error

PHP Request Shutdown: Failed to write session data (files). Please verify that the current setting of session.save_path is correct (/var/lib/php/sessions) (2)

#0 [internal function]: flight\Engine->handleError()
#1 {main}