I'm not a sysadmin but recently started using CoreOS to deploy small web apps. Could anyone explain to me like I'm 5 what's the difference between those cluster schedulers and something like CoreOS' fleet (https://github.com/coreos/fleet)?
http://www.slideshare.net/teemow1/container-orchestration
https://groups.google.com/forum/#!msg/coreos-dev/nHK8irdnmM0...
For those of us who are old school HPC people, it's probably more reasonable to think of Fleet as a dynamic always-running manifestation of xCAT or, perhaps, Fabric (of fabfile.py fame) or similar. For example, I've heard of people installing and running Mesos with it, which might seem like a bit of cluster scheduler self-satisfaction at first until one understands the reasoning.
Mesos can schedule resources for multiple different frameworks. It can run services with Marathon or Aurora frameworks. But it can also run cron jobs and batch pipelines with Chronos or Aurora. It can also schedule the distributed tasks for Hadoop or Spark.