My Book Live keeps disconnected from the network

I am using WD personal cloud storage devices: the older one is a 3TB My Book Live that I’ve bought about 2 years ago. The new one is a 4TB MyCloud that I bought in 2014. Both are connected to a TP Link router that worked quite well so far. In rare occasions I have to turn off the router and restart it. I am using a 2009 MacBook Pro with OSX Yosemite. In the past sometimes the My Book Live has been disconnected. I just have to restart it and it would work again. But in the last few days, the My Book Live keeps disconnected or even not connected even after I restart my whole equipment. I don’t have the same problem with the MyCloud. I’ve tried switching the LAN cables between the My Book Live and the MyCloud. Sometimes it would work at first but after that the problem appears again. I’m thinking of replacing the LAN cables with new ones or even replacing the router. What should I do? Any suggestions is highly appreciated.

Hi srbnst, welcome to the Community. If replacing the Ethernet cable doesn’t help, you can try setting a static IP for the My Book Live. 

How to configure a My Book Live or My Book Live Duo NAS drive with a Static IP