Taking a node down does not mean outage at all. Service uptime also reads like a non-sequitur given the comment on the JDK11 crashes sounded like OP was doing s

Taking a node down does not mean outage at all. Service uptime also reads like a non-sequitur given the comment on the JDK11 crashes sounded like OP was doing something weird with the new JDKs, not with the old prod system running JDK8. JDK11 was released way back in 2018. Any claim that it's unstable these days is not credible.