One other way of talking to a LAN device when you don't know its IP is using an ARP table entry to assign a temporary IP:
You need to know the MAC of the device.
Open the command processor ( Usually CMD)
Use the ARP command to make an entry for your NAS.
ARP help screen below, look at example #1 at the bottom
Assign an IP in your local group:
192.168.1.xxx (probably)
If you're not sure then use the ipconfig command to show the IP assigned to your PC. This will give you the first three groups.
Once an ARP entry is made you should then be able to access the device at the temporary IP number. You can then interrogate its settings.
The ARP table is hosted on your PC and is cleared after reset/reboot
Note: I use a custom command processor. Legacy of being a UNIX user from way back.
arp_help.JPGipconfig.JPG
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