So on my server, I put the server spawn limit in the bukkit.yml to 50 mobs. However, in game I am noticing that with mob grinders, people are getting over 100 mobs sometimes, I am not sure if there is another place to config the spawn limit, or if another plugin is needed. I am currently running spigot 1.7.10. Some feedback would be very helpful, thanks!
spawn limit controls natural spawning. Mob spawners are controlled by the spawner itself until the mobs exit the spawner range. You need to get a plugin that limits the number of mobs in a chunk.
If your talking about people being able to spawn animals using /spawnmob cow 20 then you need to change that limit in the essentials config otherwise you will have to do what @mactso @AllSoapedUp
There's the following (although I haven't used it): http://dev.bukkit.org/bukkit-plugins/chunkspawnerlimiter/