Running Same Minecraft Server On Two Machines At Once [closed]

A CoreOS cluster might achieve the desired effect (I'm not an expert), but the technicalities of how to set this up are too extensive to cover in this question! Clusters are complex, and I wouldn't advise trying to use one unless you're an accomplished server administrator.

You almost certainly don't want to use a cluster anyway. The main benefit of cluster computing is parallelisation; the effect is similar to having a CPU with more cores. Minecraft is almost entirely single-threaded though, meaning that extra processor cores won't really improve performance much; instead, you should aim to use faster, single-threaded processors (over 3GHz), not more (or multi-core) processors.

No, this is not possible.
Due to the way Minecraft, Bukkit and Spigot are coded, you cannot run the same instance of a server on two machines.
Minecraft worlds are locked to one instance at a time, and that instances of the software cannot share data (plus it's inefficient anyway).

The only way to do this is that you have turn off one before using another on the same set of data.

You're better off using Bungiecord to redirect one machine to the other.

Basically, servers can use the same database, but cannot use the same world.