http://www.elasticsearch.org/blog/tool-help-routing-issues-elasticsearch-1-2-0/
> In the 1.2.1 release we fixed a routing bug that had been introduced in > the 1.2.0 release. This was described in the 1.2.1 blog post. The contents > of this post apply only to users that ran 1.2.0. > Before we can discuss the tool we developed to help fix damage from the > bug, we have to understand the problem the bug created. When Elasticsearch > stores a document it has to decide which shard to put the document in. It > does this by computing a hash of the document’s “UID”, which is by default > the type#id tuple of the document. Elasticsearch then uses that hash modulo > the number of shards to pick a shard. We have to make sure that this hash > function works the same across different versions of Elasticsearch. If it > doesn’t, version X could expect to find a given document in shard 1 and > version X+1 could expect the same document in shard 2. In this case, > version X+1 could not directly get the document if it were indexed while > running version X. Regards, Mark Walkom Infrastructure Engineer Campaign Monitor email: ma...@campaignmonitor.com web: www.campaignmonitor.com -- You received this message because you are subscribed to the Google Groups "elasticsearch" group. To unsubscribe from this group and stop receiving emails from it, send an email to elasticsearch+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/elasticsearch/CAEM624Zh6-5uVn5doQuOGxQAEQa%3DZVg5RmSSMMXbVv9dgU_3-Q%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
