At some point, cts-lab stopped properly detecting log types, and the --logfile journal option was added to work around that. The log type detection works by calling syslog with a magic string then looking for that string in various locations. It worked well in the past, but now it always checks the exerciser's local logfiles first (in case it is a remote log collector), and hangs waiting for a string that never arrives. Possibly a timeout was lost at some point.