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New Member

RV042 - How to set up a network with netmask /23 on LAN?

Hello, folks.

In the company that I'm currently working, we have one gateway with LAN IP address and netmask /23 [=].

In this gateway, there's a DHCP server providing 510 IP addresses in its pool.

Network Diagram.bmp

I need to substitute the server, replacing it with a RV042. This afternoon, when I was configuring this router, I noticed that it doesn't let you configure different netmasks, since it comes with some of them predefined [starting in and so on], as shown in the picture below:

RV042 DHCP Screen.bmpI need to provide DHCP for this /23 network, but it seems that DHCP field cannot assign /23 networks.

Is there another way to circumvent this problem?

Thanks in advance for any suggestions or hints.


Luciano Areal

  • Small Business Routers
Everyone's tags (4)

RV042 - How to set up a network with netmask /23 on LAN?

Thats right I think it only supports whats in the dropdown menu. the RV series are small business router that support Class C subnets only.

the Multiple Subnet feature does allow any netmask, but not sure if that would help your situation.

Regards Simon
New Member

RV042 - How to set up a network with netmask /23 on LAN?

Hi Simon,

You're right. The RV042 User Guide tells that this device can support only Class C networks, therefore it won't fit to my needs. But, since "Google is our friend", I think I've found something interesting which may solve the problem:


In this thread, one user is asking if it's possible to change the LAN subnet mask to [/16]. The fact is in the drop down box, which has some predefined values [ to].

If you read the whole thread, you'll see that it's possible to activate Telnet service, change the subnet mask and even set up the DHCP ranges. I did these tests here but, after changing something in the web interface, the RV042 changes its subnet mask, returning it to

I'm guessing if there's a way to change the values in the web interface code.

According to what I understood, in order to make it work, I should change the values for everything in RV, apply all rules and in the end, access via Telnet and change the netmask / DHCP settings. Is that correct?

Please, any suggestion is welcome.

Thank you,


New Member

RV042 - How to set up a network with netmask /23 on LAN?


Let's put it in another way.

We have a LAN with a subnet mask

I need to put the LAN IP and configure the DHCP in order to serve a bunch of 480 computers in our branch.

Due to a limitation in web interface, I cannot assign this netmask, because it is not available in the drop down menu.

Is there a way to do it?

Thanks a lot,



RV042 - How to set up a network with netmask /23 on LAN?

if you can access a telnet session to the RV then yes you maybe able too.

if you cant access the telnet session then i guess you cant do it. problem is that DHCP on the RV042 maybe only .1-254 clients.

Regards Simon

Regards Simon
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