Access control system data loss
Environmental conditions, the environment includes: the door of the working hours, the use of access control time, whether there are local damage or details of the abnormal phenomenon. The key is to find the initial use of the problem and the normal use of the differences before, as well as changes in hardware personnel and so on.
Excluding the law, since the previous trial changes have been tried, congratulations, these problems can be temporarily considered later.
It is not the hardware that is the internal problem, but most of the situation is not the case, I encountered a similar problem, that is why I use the ping order to ping other hosts within the LAN, looking for a long time the reasons for the final line is different links (Not the other).
