Master link with slaves is down

Hi Folks,

We are having redis community version 3.0.7 with 4 nodes but we are having one issue here that is status of master slave link is down. After refering some articles and discussions, we have understand that restart/reboot of node will solve the issue. So We have tried the both options. When we restart/reboot, the staus is up and after sometime it is again down.
So could you please let us know how can we resolve this issue? and what is the impact of this status down?

Thanks