Bug when setting subnet


I (think) i’ve picked up a bug when setting my ip address with .240 subnet.

My settings:

IP Address:

Subnet mask:



When I select FINISH I get the following error:

“Subnet mask is invalid, please verify your Subnet mask and try again.”

This is very strange and only happens when setting a static ip.

my DHCP server can assing that subnet without a problem but setting it manually is NOT possible.

Please assist.

That bug has been in there a long time…

I think the folks at WD never expected anyone to have a subnet smaller than

You ought to be able to use the mask, unless you have ANOTHER subnet somewhere on YOUR network

that uses the addresses in the range 0-225 and 241-254…

But even then, it’d be doubtful your WD would be able to talk to those devices anyway, so it might not harm anything at all.

Just try it…

Hi TonyPh12345

Thank you for the reply.

If I change the subnet mask I’m worried that my router will route it somewhere else?

What do you think?

I will try setting it to and test this afternoon.


No.   A HOST’S subnet mask will not affect where a router sends packets.    A host’s mask is only relevant to the host itself.

The mask is how the host determines whether ANOTHER HOST is on the SAME SUBNET (so it will try to communicate with it DIRECTLY) or on a  DIFFERENT SUBNET (so it will try to communicate with it via its “Default Gateway.”)

If a host’s mask is set “too Big,” which is what is being described here, then it could make the Hub think that another host is on the SAME subnet, when in fact, it’s on a different subnet.

But like I said, unless you have MULTIPLE subnets in that range within your home network, you’ll be OK.

There’s very little risk of it not working with something out on the internet, because the IP range you’re using isn’t allowed on the internet anyway.