One thing to note here, is that upstream mesos is working on removing Zookeeper as a dependency. That would at a minimum remove one of the three pieces.
Note that I briefly evaluated Chronos, but tossed it aside as a toy when realizing it didn't support any form of constraints. Aurora is a very nice scheduler for HA / distributed cron (with constraints!) and long running services.
It would be fantastic if Kyle would test out Aurora, if not only to break it so that upstream fixes it. He is generally successful in breaking ALL THE THINGS.
In MESOS-1806, it mentions replacing ZK with ReplicatedLog or etcd. The replicated log is a mesos native construct, that has no external dependencies.
If you can replace ZK with a native Mesos construct, seems like it allows you to remove ZK entirely. I meant to say "optionally allow removing ZK as a dependency" in the original post. You're totally correct in that regard.
Oh I love zookeeper and have no issues whatsoever with it. However, it is almost universally the first thing I hear people moan about when someone suggest they use Mesos. People don't like Zookeeper.
The latest version of Chronos added support for constraints, at least for simple EQUALS constraints.
The annoying problem that I also encountered with Chronos was the lack of error reporting from the REST API. Invalid jobs would just return "400 Bad Request" with no error message. The error sometimes wouldn't even be reported in the logs.
Note that I briefly evaluated Chronos, but tossed it aside as a toy when realizing it didn't support any form of constraints. Aurora is a very nice scheduler for HA / distributed cron (with constraints!) and long running services.
It would be fantastic if Kyle would test out Aurora, if not only to break it so that upstream fixes it. He is generally successful in breaking ALL THE THINGS.