Dell Poweredge R710 R720 Fan Noise Control Script

fanctl.sh

#!/usr/bin/env bash
#You'll need to enable IPMI over lan in idrac first
#iDRAC Settings -> Network -> IPMI Settings
#Channel Privilege Level Limit needs to be Administrator
#You may want to create a dedicated username/pass with IPMI permission in iDRAC Settings -> User Authentication
IPMIHOST=idracip
IPMIUSER=username
IPMIPW=password
IPMIEK=0000000000000000000000000000000000000000

FANSPEEDHEX="0x08" # See https://i.imgur.com/u1HMyqI.png
MAXTEMP=60
HYSTERESIS=5

FANFILE=/var/run/autofan

function ipmi() {
        ipmitool -I lanplus -H "$IPMIHOST" -U "$IPMIUSER" -P "$IPMIPW" -y "$IPMIEK" $@
}

#For R710, which doesn't have cpu temps, try this line instead:
#if ! TEMPS=$(ipmi sdr type temperature | grep -i inlet | grep -Po '\d{2,3}' 2> /dev/null);
#thanks @bumbaclot
if ! TEMPS=$(ipmi sdr type temperature | grep -vi inlet | grep -vi exhaust | grep -Po '\d{2,3}' 2> /dev/null); then
        echo "FAILED TO READ TEMPERATURE SENSOR!" >&2
        logger -t "fanctl" -p user.err -i "Error: Could not read temperature sensor"
fi
HIGHTEMP=0
LOWTEMP=1
for TEMP in $TEMPS; do
        if [[ $TEMP > $MAXTEMP ]]; then
                HIGHTEMP=1
        fi
        if [[ $TEMP > $(($MAXTEMP - $HYSTERESIS)) ]]; then
                LOWTEMP=0
        fi
done

if [[ -r "$FANFILE" ]]; then
        AUTO=$(< "$FANFILE")
else
        AUTO=1
fi

if [[ $HIGHTEMP == 1 ]]; then
        #Automatic fan control
        ipmi raw 0x30 0x30 0x01 0x01 >& /dev/null || echo "FAILED TO SET FAN CONTROL MODE" >&2; exit 1
        echo "1" > "$FANFILE"
        if [[ $AUTO == 0 ]]; then
                logger -t "fanctl" -p user.info -i "Setting fan control to automatic"
        fi
elif [[ $LOWTEMP == 1 ]]; then
        #Manual fan control
        ipmi raw 0x30 0x30 0x01 0x00 >& /dev/null || echo "FAILED TO SET FAN CONTROL SPEED" >&2; exit 1
        ipmi raw 0x30 0x30 0x02 0xff "$FANSPEEDHEX" >& /dev/null || echo "FAILED TO SET FAN SPEED" >&2; exit 1
        echo "0" > "$FANFILE"
        if [[ $AUTO == 1 ]]; then
                logger -t "fanctl" -p user.info -i "Setting fan control to manual"
        fi
fi