One possibility is to delay the node-red start for a bit on boot to allow whatever is not ready to settle down first. To do that create a file /lib/systemd/system/nodered.timer (note, no - in nodered) and put in there
[Unit]
Description=timer for starting nodered.service
[Timer]
OnBootSec=2min
[Install]
WantedBy=timers.target
That will create a timer that will start nodered 2 minutes after boot. Tell systemd to reload its files
sudo systemctl daemon-reload
Stop node red from starting by itself (as the timer will start it)
sudo systemctl disable nodered.service
and enable the timer so it starts running on boot, and will start nodered when it times out
sudo systemctl enable nodered.timer
Then reboot. Node red should start automatically two minutes after booting. You can change the time in the timer file obviously. See if that fixes it. If not you could try a longer time, if it does then perhaps 1 minute would be enough.
