Filter events going to the logging buffer. This is a packed bit string object of which each bit has the following meaning: (bit 0 is the least significant bit). bit position meaning 8-31 reserved 7 Warning (warning conditions) 6 Notification (normal but significant conditions) 5 Informational (informational messages) 4 Error (error conditions) 3 Emergency (system is unusable) 2 Debugging (debugging messages) 1 Critical (critical conditions) 0 Alert (immediate action needed) Setting a critical level bit to 1 makes the logging buffer accept the corresponding event. Resetting a critical level bit to 0 makes the logging buffer reject the corresponding event.