The server software mandates that 1GB of ram be assigned

"Our costumers [for Realms] are parents Minecraft Resource Packs whorrrre fed up with looking to work as server administrators on the part of their kids," Mojang CEO Carl Manneh told GamesIndustry International. "Minecraft Realms is a simpler sort of service, directed at families and youngsters. In the future we try to offer certain profiles with mods which might be certified to function without crashing, but this may always be a good and simple method for kids and families to experiment with Minecraft online."

These are the minimum requirements as a way to attempt a Minecraft server.to it all the time, so having 2GB are going to be enough to own the two server and Ubuntu itself (in conjunction with some other programs which might be running). Bandwidth is additionally extremely important so as to avoid getting lag in your server, so make sure that you possess a sufficiently strong enough link to support numerous players at a time.
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