Sorry, I forgot the tl;dr on that :) If you want to know the replication factor for a given partition, you want to check the length of the replica list in the /brokers/topic/(topic) data for that partition. Note that all the partitions for a topic do not have to have the same replication factor (you can use partition reassignment to change it). But if they are not all the same, some of the tooling will break (such as altering the partition count for the topic).
-Todd On Fri, Oct 16, 2015 at 5:39 PM, Todd Palino <tpal...@gmail.com> wrote: > Actually, be very careful with this. There are two different things stored > in Zookeeper, and depending on what you're interested in you want to make > sure you're looking at the right one. > > If you want to know the replica assignment - that is, what brokers a given > partition is assigned to - you need to look at the following path: > /brokers/topics/(topic) > > The data of that znode is JSON formatted, and the 'partitions' key is a > dictionary where they key is a string representation of the partition > number (i.e. it's not 0, it's "0") and the value is a list of the replicas > that the partition is assigned to. It's worth noting that this replica list > is also the order in which the preferred leader is selected (the first > replica in the list that is in sync will be selected as the leader). > > If you want to know what the current in sync replicas are - that is, out > of the assigned replica list, which ones are currently considered to be in > sync, you need to look at the following path: > /brokers/topics/(topic)/partitions/(partition number)/state > > The data of that znode is also JSON formatted, and the 'isr' key is a list > of the replicas that are currently considered to be in sync. The important > distinction here is that this list can be shorter than the actual assigned > replica list (from the znode above) if not all of the replicas are in sync. > The state znode also has a 'leader' key which holds the broker ID of the > replica that is currently the leader for that partition. > > -Todd > > > On Fri, Oct 16, 2015 at 5:25 PM, Edward Ribeiro <edward.ribe...@gmail.com> > wrote: > >> Hey, Guozhang, >> >> On Fri, Oct 16, 2015 at 6:20 PM, Guozhang Wang <wangg...@gmail.com> >> wrote: >> >> > The replica list can be from at /brokers/topics/<topic>/ >> > partitions/<partition-id>/state >> > >> >> Nice, good to know. Thanks! :) >> >> Regards, >> Edward​ >> > >
