After i did upgrade (i.e. Uninstall 5.1.2 & then installed 5.6.15 )ElasticSearch was not comingup. We found the issue with indices. Looks like Indices (under directory /opt/elasticsearch/data/nodes/0
) does not get deleted during unintall.After I manually deleted files from that directory ,ELK 5.6.15 came up successfuly.
I want to know if there is way to up migrate indices from 5.1.2 -> 5.6.15. Since if i copy 5.1.2 indices to temporary location and later move it back after 5.6.15 installation,ELK doesnot comes up.