juju 1.25.3
environment bootstrapped with a xenial bootstrap node.
$ juju debug-log
ERROR cannot open log file: open /var/log/juju/all-machines.log: no such file or directory
rsyslog is installed but not running on the bootstrap node, which I think is a dependency for this feature:
Jan 30 09:45:44 juju-devel-xenial-machine-0 rsyslogd-2222: command 'KLogPermitNonKernelFacility' is currently not permitted - did you already set it via a RainerScript command (v6+ config)? [v8.14.0 try http://www.rsyslog.com/e/2222 ]
Jan 30 09:45:44 juju-devel-xenial-machine-0 rsyslogd-2307: warning: ~ action is deprecated, consider using the 'stop' statement instead [v8.14.0 try http://www.rsyslog.com/e/2307 ]
Jan 30 09:45:44 juju-devel-xenial-machine-0 rsyslogd-2221: module 'imuxsock' already in this config, cannot be added [v8.14.0 try http://www.rsyslog.com/e/2221 ]
Jan 30 09:45:44 juju-devel-xenial-machine-0 rsyslogd: rsyslogd's groupid changed to 109
Jan 30 09:45:44 juju-devel-xenial-machine-0 rsyslogd: rsyslogd's userid changed to 105
Jan 30 09:45:44 juju-devel-xenial-machine-0 rsyslogd-2039: Could not open output pipe '/dev/xconsole':: No such file or directory [v8.14.0 try http://www.rsyslog.com/e/2039 ]
Jan 30 09:45:44 juju-devel-xenial-machine-0 rsyslogd-2007: action 'action 14' suspended, next retry is Sat Jan 30 09:46:14 2016 [v8.14.0 try http://www.rsyslog.com/e/2007 ]
Jan 30 09:45:45 juju-devel-xenial-machine-0 rsyslogd: [origin software="rsyslogd" swVersion="8.14.0" x-pid="3744" x-info="http://www.rsyslog.com"] start
Jan 30 09:45:45 juju-devel-xenial-machine-0 rsyslogd-2222: command 'KLogPermitNonKernelFacility' is currently not permitted - did you already set it via a RainerScript command (v6+ config)? [v8.14.0 try http://www.rsyslog.com/e/2222 ]
Jan 30 09:45:45 juju-devel-xenial-machine-0 rsyslogd-2307: warning: ~ action is deprecated, consider using the 'stop' statement instead [v8.14.0 try http://www.rsyslog.com/e/2307 ]
Jan 30 09:45:45 juju-devel-xenial-machine-0 rsyslogd-2221: module 'imuxsock' already in this config, cannot be added [v8.14.0 try http://www.rsyslog.com/e/2221 ]
Jan 30 09:45:45 juju-devel-xenial-machine-0 rsyslogd: rsyslogd's groupid changed to 109
Jan 30 09:45:45 juju-devel-xenial-machine-0 rsyslogd: rsyslogd's userid changed to 105
Jan 30 09:45:45 juju-devel-xenial-machine-0 rsyslogd-2039: Could not open output pipe '/dev/xconsole':: No such file or directory [v8.14.0 try http://www.rsyslog.com/e/2039 ]
Jan 30 09:45:45 juju-devel-xenial-machine-0 rsyslogd-2007: action 'action 14' suspended, next retry is Sat Jan 30 09:46:15 2016 [v8.14.0 try http://www.rsyslog.com/e/2007 ]
Looks to be related to rsyslog bug 1531622, but I can't say yet that that's the only problem here.