Offseason FMS Networking Setup

Hi All,

We are setting up the Offseason FMS for a week 0 event here in Kansas City and I have a question for those that have used FIRST’s offseason FMS. My question concerns DHCP vs static IP address assignments.

The offseason docs say that team driver station laptops should be using DHCP, which is the case at regular season events using the full FMS. However, if I set up a driver station using DHCP, it gets an address on the 10.0.100.x subnet and the FMS never sees the driver station connection despite the fact that I can ping the FMS from the driver station laptop. If I change the DS laptop to use a static IP at 10.TE.AM.5 the FMS sees the driver station.

For right now, we are planning to use static IPs on the driver station laptops but I am hoping for an easier solution from someone experienced with the offseason FMS.


What is your networking setup?
The FIRST FMS setup uses a Layer 3 Switch and has the field network and each team on different VLAN’s (4 VLAN’s + VLAN 1). You can read more about it here.

When the match pre starts it sets up the DHCP ranges on each team VLAN.

I assume you are not using Case 33 (The Scorpion). Are you using FMS Lite (Offseason FMS)?

Have you gone through the Off-Season_FMS.pdf that came as part of the Off-season FMS zip?
Do you have the equipment recommended?

To answer both posts, I have read the documentation all the way through and we’re using the offseason FMS (FMS Lite) software. The equipment we have:

Linksys WRT1900 ACS AP, the same as FIRST uses at events.
One Ethernet switch at the scoring table.
A small 4 port Ethernet switch at each alliance station.

What we don’t have is the equipment to run a VLAN such as what FIRST has in the SCCs at events. Acquiring managed switches and developing the automated configuration that happens in match pre-start is beyond our resources at this time. Would be cool though.

What I’m trying to determine is if it’s possible for the FMS to recognize a driver station laptop with an IP in the 10.0.100.x subnet instead of at the expected 10.TE.AM.5 IP. I get the feeling that offseason events using the the offseason FMS (FMS Lite) are stuck using static IPs for the driver stations.

No. since it’s not just the Driver station. But also the Radio, rio, and any IP camera’s and co-processors.

Without the VLAN’s you will need to use static IP address’s.

And if I remember correctly. FMS lite does not know how to hand out DHCP addresses on 10.TE.AM.x

After the driver station gets an dhcp ip address, what does ipconfig show on the driver station? I suspect the DHCP server is configured to give out a netmask that doesn’t allow the DS to route packets to the FMS.
When you setup for 10.TEAM address, you set the netmask manually correctly.

The netmask is configured on the DHCP server and is sometimes difficult to set correctly for a 10.x.x.x network.

@codedr, excellent observation on the netmask. The DHCP server was feeding a netmask of I changed it to but it still didn’t work. The fact is, the DHCP server is feeding addresses on the 10.0.100.x subnet (now with a netmask of, and the FMS appears to be simply unwilling to communicate with driver stations on a subnet other than 10.TE.AM.x.

BTW, even though my driver station is on 10.0.100.x, I can ping the FMS server at and even pull up the Field Monitor web page. So, my driver station can physically communicate with the FMS server, it’s just that the FMS itself won’t acknowledge the FRC Driver Station connection at anything other than 10.TE.AM.x.

What version of FMS Lite are you using? If it’s before the switch to DHCP, the FMS actively sends packets to the DS to find the DS using the 10.TE.AM.x format.
After the switch to DHCP, the DS (no matter what ip-address) initiates the connection, and FMS uses the ip-address of the originating request to direct the DS traffic.

We’ve been using CheesyArena the last several years, and overall have been much happier than fighting ‘FMS Lite’-isms.

I’m having a hard time with the ‘FMS Lite’ option of Radio config utility. It looks like the DHCP server is still turned on in the Radio, and it’s handing out 10.TE.AM.x address to the roborio. This wouldn’t ordinarily be a problem but we broke our Access Point last year and the new AP won’t currently let me config for the network.

I’m using the Offseason FMS 2018 - the latest that is available. I want to switch to Cheesy Arena for next year and invest in a managed switch so we can run a VLAN at our next week 0.

The FRC Radio Configuration tool, when run in FMS Lite mode, sets the radio to bridge mode and enables a DHCP server on the robot radio that is supposed to provide a DHCP reservation of 10.TE.AM.2 to the Robo Rio.

You may want to consider running a different DHCP server on your FMS LAN if your AP won’t let you set a class A netmask. There are several open source / free ones for Windows. Otherwise, you would need each team to set a static IP on their robo rio AND their driver station.

One workaround would be to NAT the proper addresses and assign each team a static.

For example:
Team 1987 would normally have 10.19.87.X but you would route it to be 10.0.100.X

Original address: 10.19.87.X
Translated address: 10.0.100.X

This could be done through any decent firewall or by pfsense, though I am not sure you would want to invest time into doing this. The result would mean that FMS lite doesn’t notice any difference between the IPs but I believe you would have to change configurations depending on which team is on which side of the field.

If you want to use Chessy Arena next year make sure you buy a Layer 3 Switch since you need to be able to route between VLAN’s
As for sourcing a switch, ebay and craigslist have an abundance of cheep Cisco gear.