Neo4j PID File Location

Hello,

I'm using Neo4j Causal Cluster consists of 3 core servers.

Details of the cluster:
Neo4j Version: Neo4j Enterprise 4.3.6
OS: Ubuntu 20.04.3 LTS

As per the Neo4j Doc File locations, the PID file should locate inside /var/lib/neo4j/run.
But there I couldn't find the /var/lib/neo4j/run directory or PID file.

I'm trying to implement Monit monitoring for the neo4j process and I need the neo4j service PID file location for that configuration.

Appreciate your support to find the PID file location for the neo4j service.

Thanks all