With the per-collection state.json, if "something" goes to a node that doesn't host a replica for a node, it downloads the state for the "other" collection then throws it away.
In this case, "something" is apparently asking the nodes hosting collectionA to do "something" with collections B and/or C. Some support for this would be if further investigation shows that the nodes that _do_ re-download the info did _not_ have replicas B and C. What the "something" is that sends requests I'm not quite sure, but that's a place to start. Best, Erick On Mon, May 16, 2016 at 11:08 AM, Jeff Wartes <jwar...@whitepages.com> wrote: > > I have a solr 5.4 cluster with three collections, A, B, C. > Nodes either host replicas for collection A, or B and C. Collections B and C > are not currently used - no inserts or queries. Collection A is getting > significant query traffic, but no insert traffic, and queries are only > directed to nodes hosting replicas for collection A. ZK timeout is set to 15 > seconds. > > I’ve noticed via tcpdump that, every 10 seconds exactly, several of the nodes > (but not all) hosting collection A re-download the state.json for collections > B and C. This behavior survives JVM restart. > > This isn’t a huge deal, the extra traffic isn’t very meaningful, but it’s odd > and smells like a bug somewhere. Anyone seen something like this? > >