Just upgraded from UnRAID v4.7 to v5.0.4 and so far had positive experience with this modified sleep script, which I used in v4.7:
#!/bin/bash
# Table of all possible drives when all drive slots are fully populated, with usb boot flash "/dev/sda" excluded
drives="/dev/sdb /dev/sdc /dev/sdd /dev/sde /dev/sdf /dev/sdg /dev/sdh /dev/sdi /dev/sdj /dev/sdk /dev/sdl /dev/sdm /dev/sdn /dev/sdo"
# Timeout in minutes
timeout=60
count=$timeout
while [ 1 ]
do
hdparm -C $drives | grep -q active
if [ $? -eq 1 ]
then
count=$[$count-1]
else
count=$timeout
fi
if [ $count -le 0 ]
then
# Do pre-sleep activities
sleep 5
# Flush hdd filebuffers
sync
# Go to sleep
echo -n mem > /sys/power/state
# Do post-sleep activities
# Flush hdd filebuffers
sync
# Force NIC into gigabit mode
# (might be needed forgets about gigabit when it wakes up)
ethtool -s eth0 speed 1000
# Force a DHCP renewal (shouldn't be used for static-ip boxes)
#/sbin/dhcpcd -n
sleep 5
count=$timeout
fi
# Wait a minute
echo COUNT $count
sleep 60
done