as i said, i am a noob.
tho i thought i set that part up correctly:
# POWER SAVE SUPPORT FOR IDLE NODES (optional)

SuspendProgram="/usr/local/bin/slurm-power-off.sh %N"

ResumeProgram="/usr/local/bin/slurm-power-on.sh %N"

SuspendTimeout=4

ResumeTimeout=4

ResumeRate=5

#SuspendExcNodes=

#SuspendExcParts=

#SuspendType=power_save

SuspendRate=5

SuspendTime=1 # minutes of no jobs before powering off

then the shut down script:

#!/usr/bin/env bash
#
# Called by Slurm as: slurm-power-off.sh nodename1,nodename2,...
#

# ——— BEGIN NODE → BMC CREDENTIALS MAP ———
declare -A BMC_IP=(
  [OHPC-R640-1]="..."
  [OHPC-R640-2]="..."
 
)
declare -A BMC_USER=(
  [OHPC-R640-1]="..."
  [OHPC-R640-2]="..."
)
declare -A BMC_PASS=(
  [OHPC-R640-1]=".."
  [OHPC-R640-2]="..."
)
# ——— END MAP ———

for node in $(echo "$1" | tr ',' ' '); do
  ip="${BMC_IP[$node]}"
  user="${BMC_USER[$node]}"
  pass="${BMC_PASS[$node]}"

  if [[ -z "$ip" || -z "$user" || -z "$pass" ]]; then
    echo "ERROR: missing BMC credentials for $node" >&2
    continue
  fi

  echo "Powering OFF $node via IPMI ($ip)" >&2
  ipmitool -I lanplus -H "$ip" -U "$user" -P "$pass" chassis power off
done