Unfortunately, there was a bug in our NTP package that caused a crash on CCR units due to the introduction of the Leap Second on June 30, 2015. This bug did not cause any other problems. We have fixed the issue in RouterOS v6.30rc26. No other devices were affected, only CCR units.
We are sorry for the inconvenience, please upgrade the devices when the new v6.30 version comes out, or upgrade to the RC now, if you prefer to get the fix sooner. The fix will also prevent any problems with further leap seconds in the upcoming years.
In addition, we also improved the Watchdog to do it's job better and make sure the devices are rebooted in this type of crash.
Download v6.30rc26 here: http://www.mikrotik.com/download/share/ ... 30rc26.npk