Static IP vs DHCP

[onenerdyguy]

Last year, we had a heck of a time with connectivity dropping, and not 100% sure why. Things like the camera feed via mjpg wouldn't load up reliably and the like. While I'm sure a part of it was bandwidth, I'm wondering if a part of it could be also be mdns configs vs using static IPs. I've personally never had much luck with MDNS in other projects.

Is there a concern by statically configuring IP's for myd river station, roborio, and co-processor as long as their in the correct team number subnet, i.e. 10.59.29.xx for us, 5929?

[marshall]

Originally Posted by onenerdyguy

Last year, we had a heck of a time with connectivity dropping, and not 100% sure why. Things like the camera feed via mjpg wouldn't load up reliably and the like. While I'm sure a part of it was bandwidth, I'm wondering if a part of it could be also be mdns configs vs using static IPs. I've personally never had much luck with MDNS in other projects.

Is there a concern by statically configuring IP's for myd river station, roborio, and co-processor as long as their in the correct team number subnet, i.e. 10.59.29.xx for us, 5929?

Team 900's expert advice:

1) Use Static IPs where possible.
2) Ensure gateways and subnet masks are set correctly.
3) Ensure connectivity of vital components prior to start of the match by building a dashboard or script.
4) Don't use the words 'balls' and 'fuel' interchangeably on ChiefDelphi.*

* This one isn't strictly related and hasn't been tested yet.

[ATannahill]

There should be no concern but I would recommend telling any FTA/FTAA/CSA that is working with your robot that you intentionally set static IPs so they do not assume that you are on mDNS.

Items 2 and 3 and 4 on Marshall's list are great points.

[brian5115]

At CHS last year we were having similar issues so we talked to an FTA that basically said she thought FIRST had switched to MDNS prematurely, and the FMS couldn't keep up with all the robots. She told us to switch to static IPs and our issues disappeared.

Just for reference, we had two Axis cameras and a Raspberry-Pi on the network in addition to the robo-RIO and driver laptop.

[marshall]

Originally Posted by ATannahill

There should be no concern but I would recommend telling any FTA/FTAA/CSA that is working with your robot that you intentionally set static IPs so they do not assume that you are on mDNS.

This is also a good point. Do make sure any FTA's know what you have done if you are troubleshooting it with them.

[onenerdyguy]

Awesome, that was the answer I was hoping for. I agree, mDNS was a bit premature, and as a working network professional myself, I'm not a fan of it in the first place.

Since we're a python shop, our interactions with the majority of FTA/FTAA/CSA is limited due to the non-supported nature, but it's a good thing to keep in mind.

as for #4, I'd like to put that should apply to the majority of discussions in person as well. We had a few interesting design discussions about how our robot would be good at ball handling, would store balls in a ball sack, and that we should find a way to empty the ball sack quickly and accurately with our shooter.

[virtuald]

To echo what others have said, mDNS and static IP are equally supported by FIRST, and maybe one day mDNS will actually work. But I recommend anyone doing dashboards/coprocessors/etc to use static IPs.

[rich2202]

My team uses Static IP's, and have avoided a lot of problems.

Make sure you use the default addresses. I believe they are:
10.XX.YY.zz

Where XXYY is your team number

ZZ is
1 Radio
5 RoboRio
10 Driver Station
12 Camera

I'm sure if I am wrong, someone will correct me.

[ATannahill]

Originally Posted by rich2202

My team uses Static IP's, and have avoided a lot of problems.

Make sure you use the default addresses. I believe they are:
10.XX.YY.zz

Where XXYY is your team number

ZZ is
1 Robot Radio
5 2 RoboRio
10 5 Driver Station
12 11 Camera

I'm sure if I am wrong, someone will correct me.

I have put in the recommended way to set static IPs and how I do it as a CSA. Other things might work.

[marshall]

Let's see if we can't resolve this properly:

https://frc-qa.firstinspires.org/qa/90

[ATannahill]

Originally Posted by marshall

Let's see if we can't resolve this properly:

https://frc-qa.firstinspires.org/qa/90

Have you reviewed this?

I am all for letting teams stick with what they found has worked, I was posting what I used for reference for anyone new to setting their own static IP addresses.

[marshall]

Originally Posted by ATannahill

Have you reviewed this?

I am all for letting teams stick with what they found has worked, I was posting what I used for reference for anyone new to setting their own static IP addresses.

In fact, I had not. From that link for others to reference:

It is also possible to configure static IPs on your devices to accommodate devices or software which do not support mDNS. When doing so you want to make sure to avoid addresses that will be in use when the robot is on the field network. These addresses are 10.TE.AM.1 and 10.TE.AM.4 for the DAP1522 radio and the field access point and anything 10.TE.AM.20 and up which may be assigned to a device still configured for DHCP. The roboRIO network configuration can be set from the webdashboard.

DAP1522 radio - Static 10.TE.AM.1 programmed by Kiosk
roboRIO - Static 10.TE.AM.2 would be a reasonable choice, subnet mask of 255.255.255.0 (default)
Driver Station - Static 10.TE.AM.5 would be a reasonable choice, subnet mask must be 255.0.0.0
IP Camera (if used) - Static 10.TE.AM.11 would be a reasonable choice, subnet 255.255.255.0 should be fine
Other devices - Static 10.TE.AM.6-.10 or .12-.19 (.11 if camera not present) subnet 255.255.255.0

I'm glad that is in screensteps with no mention of it in the manual.

EDIT: On the plus side, just threw the Q&A team a softball.

[wilsonmw04]

We had some interesting times trying to connect to the field at he beginning of the season. It was suggested we try a static IP by our awesome FTA and the connection problems disappeared. I so no downside to setting static IP's on your 'bots as long as you put each item in the expected range.

[scca229]

Going to just highlight this one from marshall's post.

Driver Station - Static 10.TE.AM.5 would be a reasonable choice, subnet mask must be 255.0.0.0

When there is a communication problem on a DS and they have informed me they are using static IPs, or I drag it out of them after getting the deer-in-the-headlights look when I ask, this is very often the issue. Everyone is so used to using /24 submasks (255.255.255.0) when this particular one must be a /8 (255.0.0.0). The funny thing is that most versions of Windows that I know of automatically default to a /8 when you enter a 10. IP.

[billbo911]

This is one area that I have a strong opinion on.

If reliability is one of your team's goals for the season, then why take a risk on mDNS?
Yes, usually mDNS works just fine. But, I did say usually.

Why not just lock down your IPs to KNOWN values and move on.
They won't change, you know where each device is addressed, and connections on the field will JUST WORK! What more could you ask for?
Well, OK, you could ask for an easy to find guide to setting your IP's statically. Fortunately, this thread already has what you really need to know.