You are actually not alone in these on and off scenario. There are many gamers out there who would tell the same exact story: They are going on with their usual stuff when suddenly and without warning they would get disconnected, along with an error message displayed on their screen saying "The connection to the server was lost", followed by ps3 D5027 code.

PS3 Home Error D5027: Knowing the real issue

Well the problem with ps3 home error d5027 is really very simple. While it is still in the beta stages, things are still a bit unstable since many people are very eager to get in, thus the network gets congested.