MySQL Error!

The Error returned was:
Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (111)

Error Number:

Warning: Unknown: open(/var/lib/php/session/sess_b9gkj9qqa7k9fdtkiker6sjtf3, O_RDWR) failed: Read-only file system (30) in Unknown on line 0 Warning: Unknown: Failed to write session data (files). Please verify that the current setting of session.save_path is correct (/var/lib/php/session) in Unknown on line 0