Definition - What does Lurking Server mean?
A lurking server is a piece of hardware that may be in an existing architecture, but does not get a lot of attention. In many cases, lurking servers show up after being disregarded for a while, as a result of scaling processes where the company keeps building onto a hardware setup without really taking stock of what is already there.
Techopedia explains Lurking Server
In the world of network virtualization, the issue of lurking servers remains a challenge. Companies may scale up quickly to get a certain level of performance, but they might not be getting optimized performance out of each individual server. In some cases, lurking servers are carrying obsolete software, which is why they were initially passed over in the first place.
One solution for eliminating lurking servers is to do a comprehensive server inventory. With inventory management tools, technicians can figure out how to manage server sprawl, and how to optimize a very distributed network. Essentially, it is all about documentation of existing hardware and a detailed look at how a network works, where server workloads are, and how to either upgrade or remove lurking servers as necessary.