We began experiencing failed VNC connections to the console display on servers that have been updated to EL 6.3. No such failures have occurred on similar connections to EL 6.2 servers.
On the client machine a normal VNCviewer display appears with the expected graphical login until the mouse pointer is moved within the boundaries of the VNCviewer window. At this point the window closes and an error message appears in both a pop-up window and in the terminal window in which the session was initiated stating “read: Connection reset by peer (104)”.
On the server end, a core dump is generated and a abrt bug report is created.