I am experiencing an assertion failure when I log to first a usertty destination, then a file destination. (In the reverse order, things seem to be OK. Logging to two files seems OK). I did some tracing, and while I got rather lost in the reference counting and acking logic, I did find out that a call to log_msg_ack() in afuser_dd_queue() is dropping 2 references to a message when there apparently aren't 2 to drop, resulting in an eventual attempt to unreference the message when its reference count is zero, which the code asserts is impossible. I then noticed that none of the other af*.c files call log_msg_ack() at all, and thought maybe that call doesn't belong there. The message that's triggering the problem is the "syslog-ng starting up" message. The reason log_msg_ack() drops two references is that there are two ack thingies attached to the message: one with a log_center_ack() callback and one with a log_source_msg_ack() callback. I can add more details, such as a config file, if necessary, or do some more tracing. -- Bryan Henderson San Jose, California