I've been working with many of you in the past few weeks and you all have been ULTRA HELPFUL. SO thanks for that.
With that said, I'm finalizing my final setup / re-install and want to verify this works...
I had a 5.5.1 ES Cluster with specialized nodes that is working great. During an upgrade of Ubuntu, the ES and Service was completely removed... Why... ???
So since I have to re-install ES and our ES 5.5.1 Data is on an external Volume that is still intact, we are going to resetup the servers, but this time install ES 6.8.15 (I was told this version of ES can fully utilize our ES 5.5.1 data indexes (Nothing prior to 5.5.1 was made, so all the indexes are 5.5.1).
So first re-assure, is I want to make sure that my re-install of 6.8.15 can fully utilize my 5.5.1 indexes?
Next, I know i have to use at least JDK 8 for Elastic, if I just install the lastest and great OpenJDK on my ubuntu 18.04 servers, will that still work with ES 6.8.15 and above?
Also final question,
We are installing Ubuntu 18.04 due to compatability with Elastic and Kibana and such. Is 20.04 not fully yet compatiable with the latest version of Elastic and Kibana and such (we will be upgrading to the latest 7.x later and trying to see if I can just install 20.04 or should we stick with 18.04 for best level of compatibllity with the full ES stack (ES, Kibana and such)