PBS-server not running

Thank you for sharing the above details @nmazeh

  1. You can update your script as below

#!/bin/bash
#PBS -l select=1:ncpus=1
#PBS -l walltime=24:00:00
#PBS -N Finding_pi_serial
#PBS -m abe
#PBS -M mazeh01@hotmail.com
cd $PBS_O_WORKDIR
/home/pi/demo/fpi-serial

Quick query:
0. Please share us the output of these commands

cat /etc/pbs.conf
qstat --version

  1. is /home/pi/demo/fpi-serial accessible on Pi01 and Pi02 ? is /home common across PBS Server and PBS Compute nodes ?
  2. Please check and share whether the services are running on PBS Server and PBS Compute Nodes by running the below command

ps -ef | grep pbs_

Please start the PBS services once more and check systemctl start pbs or /etc/init.d/pbs start

source /etc/pbs.conf
cd $PBS_HOME/server_logs # location of pbs server logs
cd $PBS_HOME/sched_logs # location of pbs sched logs
cd $PBS_HOME/comm_logs #location of pbs_comm logs

On the compute node, the mom logs are seen here ( /etc/init.d/pbs start)

source /etc/pbs.conf
cd $PBS_HOME/mom_logs #location of PBS MOM logs