On Wed, Apr 22, 2015 at 2:57 PM, Ken Dreyer <kdreyer@xxxxxxxxxx> wrote: > I could really use some eyes on the systemd change proposed here: > http://tracker.ceph.com/issues/11344 > > Specifically, on bullet #4 there, should we have a single > "ceph-mon.service" (implying that users should only run one monitor > daemon per server) or if we should support multiple "ceph-mon@" services > (implying that users will need to specify additional information when > starting the service(s)). The version in our tree is "ceph-mon@". James' > work for Ubuntu Vivid is only "ceph-mon" [2]. Same thing for ceph-mds vs > ceph-mds@. > > I'd prefer to keep Ubuntu downstream the same as Ceph upstream. > > What do we want to do for this? > > How common is it to run multiple monitor daemons or mds daemons on a > single host? For a real deployment, you shouldn't be running multiple monitors on a single node in the general case. I'm not sure if we want to prohibit it by policy, but I'd be okay with the idea. For testing purposes (in ceph-qa-suite or using vstart as a developer) it's pretty common though, and we probably don't want to have to rewrite all our tests to change that. I'm not sure that vstart ever uses the regular init system, but teuthology/ceph-qa-suite obviously do! For MDSes, it's probably appropriate/correct to support multiple daemons on the same host. This can be either a fault tolerance thing, or just a way of better using multiple cores if you're living on the (very dangerous) edge. -Greg -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
