You should take note of the compatibility breaking changes in the release notes of course and do some functional tests with the new version to ensure that you are not affected by those changes. Additionally, I would carefully plan and test the update procedure with a smaller cluster first. In theory, you should be able to do a rolling restart with the new version but that still is a somewhat risky procedure where there is some room for unexpected outages. Doing upgrades like this without any downtime can be challenging.
The easiest is to just shutdown the whole cluster, upgrade all the nodes and then bring it back up. When I did this a few weeks ago with my logstash cluster (0.90.8 -> 1.0.0), it spent about 15 minutes converting my indices before the cluster went green again. That was a small setup with only 10GB. The differences between 0.90.5 and 1.0.0 are not such that I would perform any upgrades to in between versions. The risks for those upgrades are similar to doing the proper upgrade to 1.0.0 directly probably. You'd have to deal with several lucene updates and index conversions. Jilles On Thursday, February 27, 2014 10:00:45 AM UTC+1, hrishikesh prabhune wrote: > > Hello all, > I have a huge elasticsearch cluster with around 150 Tb of data indexed > into it. It has 32 nodes and more than 3000 shards in active state. I am > planning to upgrade this elasticsearch cluster from version 0.90.5 to > 1.0.1. Are there any index compatibility issues that I need to be aware > of? I know that 0.90.5 is based on lucene 4.4 and 1.0.1 is based on lucene > 4.6.1 (correct me if im wrong) I am not quite sure about the codecs > compatibility between these versions of lucene indices. Can anybody shade a > light on it? > Are there any pointers or issues that I need to look out for in order to > do the upgrade? Also I am not planning to do a rolling upgrade. So I am not > worried about transport client compatibility issues. > Thanks in advance!! > -- 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/13be09f0-4d10-4664-a56a-6d449cdca057%40googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
