I am currently planning an upgrade from ELK 6.6 to 7.4.2 but I would like to do this as rolling upgrade because having the entire cluster restart or down is not an option. According to the documentation, full cluster restart seems to be the only possible way of upgrading directly from 6.6 to 7.4.2:
I would like to know if a rolling upgrade is possible and if yes:
- What are some of the things I might need to keep in mind for this procedure
- Is there any documentation for the best possible practices to be followed for such an rolling upgrade between major versions?
- How should the data migration be taken care of when upgrading between 6.6 to 7.4? Can we just follow normal rolling upgrade steps or do we need reindexing or some procedure like that to be followed?