Redstone clock

[predator_ox]

Why when i want to do a redstone clock, the signal dissapears.
Is because of lag or its because of the server?

 

[Yanique1]

If you unload the chunks red stone problems can occur. This also may be a feature to reduce server lag

 

[The_W]

It's because of a plugin to prevent from lagging the server.
Basically, fast redstone clock mechanism, or any redstone mechanism that ticks on and off repeatedly and rapidly in a short time will be shut down entirely after a short time (All redstone signal within the mechanism will off including redstone torch).

Solution
So, if you still need to use redstone clock mechanism, try to make it slower, much much slower until it works out. Add more delay on redstone repeater or add more repeater to the mechanism.