On Fri, May 14, 2021 at 5:13 PM jerome moliere <jer...@javaxpert.com> wrote: > > Hi all, > I would like to know the best practices to migrate a mission critical Solr > cluster from version 6.x to 8.x without any service shutdown. > Is the double upgrade required (mandatory) ? > We can introduce another temporary group of machines ro join the cluster, > then we may stop the existing nodes one by one once upgrade done... > In this case we have different indexes and 2 replicas per shard... > > Is it possible to have concurently 2 versions of SolR running in the same > cluster? > Of course a full reindexing seems to be required , there is no problem we > have enough time ( upgrade procedure is not required to be finished in a > short time). > I would like to have a summary of options available , pros & cons for each > one and if possible a few tips & tricks to avoid some pitfalls... > > If you have good pointers to share and any feedback from production > upgrades they will be welcome... > Thanks for your help . > Kind regards
With the (lack of) constraints mentioned here I think the easiest path is a new cluster, full re-index, and then swap over your clients.
