Trying to install 1.18.9 plugin on a node running 7.5.0. Had to switch from the java shipped with ES as it was broken for several reasons - am using
java-1.8.0-openjdk-188.8.131.52.b09-0.el7_7.x86_64 which is the latest java for this CentOS 7.7 system.
Starting ES I get a bunch of stack traces but the key error looks to be:
Caused by: java.lang.UnsupportedClassVersionError: tech/beshu/ror/Constants has been compiled by a more recent version of the Java Runtime (class file version 53.0), this version of the Java Runtime only recognizes class file versions up to 52.0
Suggestions? I had RoR running on 7.4 previously (different system) using the system java. I tried to download the 7.4.2 and see if I could downgrade ES and have it start working again, but I got a “Oops something went wrong. Contact us directly” message on the download page.