Im looking to better understand this piece of advice in relation to setting up devices on internal networks with static IP addresses, and why that is considered a bad idea.
On the surface of it, setting up static IP addresses for devices on an internal network that acts as a server doesn't seem like a particularly bad idea when those servers need to communicate with each other regularly. If server A needs to request a web page or an FTP connection or whatever from server B, the task is made much simpler by making sure that server B can always be found at a specific address instead of searching through the network for server B each time.
The only immediate issue that I can think of when setting a static IP address is that the IP address is defined from the servers side and not the router (e.g. the server says to the router, "I want to be connected to your network at IP address
192.168.0.42"). This is fine in most simple cases, but if there's a collision (two different devices are both asking/demanding to be
192.168.0.42), the setup is bound to fail somehow.
Beyond that one case though, why is setting up servers on an internal network with static IP addresses such a bad idea?