The main scenarios for us are upgrading NiFi and updating (and consequently restarting) the Kubernetes workers for security updates. Both of these make manual offloading basically impossible - the StatefulSet handles pod restarts by itself, and the Kubernetes control plane drains and restarts worker machines automatically.
Regards, Alexis. On Sat, 17 Aug 2024, 17:40 Joe Witt, <[email protected]> wrote: > Alexis > > Yep we totally understand. > > What scenarios are you trying to plan/design for that require restarts? > > Thanks > > On Sat, Aug 17, 2024 at 8:24 AM Alexis Sarda-Espinosa < > [email protected]> wrote: > >> Hi Joe, >> >> I agree the system can recover after the restart, but we want to deliver >> data with as little latency as possible, so if FlowFiles stay queued during >> the restart time window, by the time the node is up and running again the >> data will be very late when time it finally leaves the NiFi cluster. >> >> Regards, >> Alexis. >> >> On Sat, 17 Aug 2024, 16:59 Joe Witt, <[email protected]> wrote: >> >>> Alexis >>> >>> >>> If you are simply restarting nodes you dont need to ensure everything is >>> processed first. It will recover. >>> >>> If you want to scale down by removing a node there is an api to invoke >>> offloading so you could scale down to a single node even if needed. >>> >>> Thanks >>> >>> On Sat, Aug 17, 2024 at 2:02 AM Alexis Sarda-Espinosa < >>> [email protected]> wrote: >>> >>>> Hello, >>>> >>>> We use NiFi in cluster mode in Kubernetes via a StatefulSet. Sometimes, >>>> we need to restart the cluster, so the StatefulSet restarts one pod at a >>>> time. In this scenario, will a given node attempt to process all >>>> "in-flight" FlowFiles to drain the queues as much as possible before >>>> shutting down? >>>> >>>> I know it's probably impossible to have a completely graceful offload >>>> in these cases, but since the process still receives a termination signal >>>> and has some time before it must stop, it could try to prevent FlowFiles >>>> from staying in the system for too long, but I don't know if there are any >>>> mechanisms to handle this in NiFi. >>>> >>>> Regards, >>>> Alexis. >>>> >>>
