On Tuesday, April 29, 2014 10:15:35 AM UTC-5, Christopher Wood wrote: > > > Can't hosts already stagger their agent checkin times by using per-host > runinterval settings? > >
No. Different agents with different runintervals will still all hit the server at nearly the same time when they are started together, and they will do so again periodically thereafter (just not every run). Moreover, it's nasty to use a policy knob such as runinterval to address a technical issue such as avoiding a thundering herd effect. Puppet does have the 'splay' and 'splaylimit' configuration settings as a possible solution, however. If you can accept some variation in the interval between one agent run and the next then those are pretty effective, albeit non-deterministic. > At some point, sure, agents may not be the best path forward but I don't > see when I'd reach that point. > > I'm uncertain whether by "agents" you mean running the agent as a service, or whether you mean using the agent at all (as opposed to using "puppet apply"). Garrett was not suggesting the latter; he was suggesting using cron to schedule runs of the agent in non-daemon mode. You can also schedule runs of "puppet apply" that way, but that's a whole different ball game. There is a lot to be said for scheduling the agent via cron. In addition to possible applications in load leveling, it can make Puppet more resilient. For example, I was recently working on the provider of a custom type, and I managed to let a broken version escape to some of my systems, where it crashed the agent daemon. I had to manually restart the daemons on those systems. If I were launching Puppet from cron then the Puppet runs would still have failed, but the next runs, when a fixed version of the provider was available, would have gone fine without any manual intervention. In addition, where Puppet manages its own configuration, launching it via cron is much cleaner. Not necessary, as I understand it, but cleaner and therefore less open to unexpected behavior. In the past, people have launched Puppet that way also to avoid creeping memory usage, though I think those memory problems are solved in any recent Puppet. On the other hand, the system service infrastructure is a bit more natural and simpler to use than is cron. Nevertheless, for my own site I have vague plans to switch from running Puppet as its own service to launching it via cron, at some indefinite point in the future. John -- You received this message because you are subscribed to the Google Groups "Puppet Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to puppet-users+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/puppet-users/c0aa9f0c-7730-481e-b026-8ac80df43a5f%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
