[Solved] DHCP Issue

[elfege]

I’ve been using Hubitat for years. You probably remember me from when I was a clueless beginner. Fair. I asked rookie questions. I learned.

But here's the part you seem to have missed: I evolved. You didn’t.

I now manage enterprise-grade networks. SonicWall firewalls, segmented VLANs, NAT rules, DHCP with static reservations, ARP cache management — daily stuff.
Your hub is the only device that keeps screwing up the basics.

Here’s the repeat offense:

• Reboot the hub.
• Solid green light says "I'm fine!"
• But it’s not fine. It clings to an old IP and ignores its DHCP reservation.
• SonicWall shows no active lease for its MAC.
• The hub refuses to announce itself with a gratuitous ARP.
• Stays invisible until I physically unplug/replug its Ethernet cable.

That’s not acceptable behavior for a “smart” hub in 2025.
It’s bad engineering. Period.

To make it worse:

• There’s no CLI access.
• No way to SSH in and force a DHCP renew.
• No diagnostic tools.
• Nothing but the medieval “pull the plug” method.

That’s design laziness. You chose to build a black box product that users can’t even troubleshoot. When it works, great. When it breaks, tough luck — start yanking cables.

Meanwhile, every other device on the same network — including $20 smart plugs — negotiates DHCP leases and announces itself like a good network citizen.

This is not SonicWall's fault. It’s not user error.
It's your device refusing to follow basic DHCP client standards.

What you should have fixed years ago:

1. Proper DHCP renewal after reboot.
2. Gratuitous ARP announcements.
3. Admin-accessible CLI for diagnostics and forced network renegotiation.

But no. You keep suggesting paperclips to reset the network stack. In 2025.

I’m done sugarcoating it:
Hubitat hubs are fundamentally broken when it comes to DHCP handling.

And the fact that this is still a thing shows me you’re either unwilling or incapable of fixing it.

I’m not here to whine. I’m here to tell you, bluntly:
You’ve failed to evolve with your user base.

[EDIT / UPDATE]
While my initial post was sparked by a local error on my part (already addressed in a follow-up), the broader concerns about Hubitat’s DHCP behavior and network tooling remain valid.

This isn’t about blame — it’s about recognizing certain limitations that surface in more advanced network environments.

The real technical concerns:

• Lack of CLI / Diagnostics
  Hubitat offers no command-line access, no SSH, and no way to manually trigger DHCP renewals or diagnose network-level issues.
  This design choice prioritizes simplicity, but leaves power users without essential troubleshooting tools.
• Inconsistent Gratuitous ARP Behavior
  Hubitat hubs do not reliably send gratuitous ARP broadcasts after reboot.
  This can lead to ARP cache desynchronization on enterprise-grade routers and firewalls, requiring manual intervention.
• DHCP Lease Handling Edge Cases
  In certain environments (e.g., SonicWall DHCP servers), hubs have been observed to retain old IPs after reboot, ignoring correct DHCP reservations.
  While this may not affect every user, it does highlight a gap in DHCP client robustness.

A note of respect:
I recognize that Hubitat remains a relatively small team, and the work they’ve done to deliver a powerful, local automation platform is impressive. My frustration in the original post overshadowed that fact, and for that, I apologize.

This feedback is intended constructively. These network-level quirks might seem niche, but they represent real friction for users managing segmented or enterprise-class networks alongside their Hubitat hubs.

And for @dennypage (since you asked for actual data):
This thread itself already proves the point. The fact that advanced users keep encountering these DHCP quirks — and have no built-in tools to diagnose them — is the evidence.
We're not talking about exotic features, just basic network hygiene that every other IoT device handles gracefully.

Others have faced the same issues and have provided actual packet captures to document them (which is why I didn’t need to repeat the exercise here):

Problems Changing Hubitat Static IP to DHCP

Hello, So recently I had some issues changing my IP address from a static one to DHCP (as I was hoping that I could assign the device a 'static' address from my router). However, I feel like the issue I have now is one that I can't resolve myself (which is why I emailed support with no response other than the canned one). From the hubitat's web portal, I changed static IP assignment to DHCP, expecting that my router would be able to assign it a new address the address range I specified from my…

Thanks again to those who provided useful feedback, and to the Hubitat team for continuing to support the platform.

—

[elfege]

Update:
Okay, plot twist. Turns out I was looking at the wrong hub.
Hub 1 was off — because I shut it down via settings — and, being colorblind, I mistook another hub’s LED as red when it wasn’t. Hub 1 is in the stairwell, not the office. So yeah, user error.

But here’s the thing:
This doesn’t change the core issue.

I still have:

• Hubs that fail DHCP renewals after reboot.
• No gratuitous ARP.
• No CLI access to force network re-negotiation.
• A product that assumes a static, utopian network where nothing ever goes wrong.

So while this was on me (I’ll wear that L proudly), the underlying problem persists.
I shouldn’t have to go hunt for a stairwell hub to physically replug it after a DHCP lease issue.
And I shouldn’t be stuck poking paperclips in 2025 because there’s no real admin access.

[JumpJump]

@elfege

I shouldn’t have to go hunt for a stairwell hub to physically replug it after a DHCP lease issue.

This is weird, friend. Why is it a hunt? Got your hyperbole turned up.

I don't have your issue. I also solve any need for a power cycle using poe. Never needed it.

I run unifi. No problems. Could be a chair keyboard issue.

[csteele]

@elfege

Hubitat hubs are fundamentally broken when it comes to DHCP handling.

And the fact that this is still a thing shows me you’re either unwilling or incapable of fixing it.

Incapable is completely wrong and included only for braggadocio or stupidity. <-- see how that's the same as what you did?? You may want to argue with your wife and kids that way, but we're neither.

Unwilling is not correct either. "Satisfied with the way it works" is probably more correct. Enough people have pointed out the way THEY want it to work, and yet it continues to work the way that is best for Hubitat's interpretation of their customer's needs.

Ok, you don't like the way it works, un-constructive criticism received. Can we move on?

[user5298]

@elfege

You probably remember me from when I was a clueless beginner. Fair. I asked rookie questions. I learned.

But here's the part you seem to have missed: I evolved. You didn’t.

I now manage enterprise-grade networks. SonicWall firewalls, segmented VLANs, NAT rules, DHCP with static reservations, ARP cache management

Congratulations on your advancement from a clueless beginner, to an expert in these highly complex aspects of networking. I'm certainly impressed.

I am embarrassed to say that with my limited knowledge of networking, I didn't even know this problem existed. So thanks for pointing out what Hubitat has obviously been hiding from us all these years.

I am considering switching to another hub based on your findings. I'm sure many other owners feel the same way.

Would you consider bailing Hubitat out of this mess by providing them with the solution to the issue.

[dennypage]

There is a lot of speculation and assumptions here. This is not the kind of posting I would expect from someone who manages enterprise networks.

If you want to assert that Hubitat's DHCP implementation is misbehaving, set up span ports and capture packet traces. Show the packets, and make your point with evidence rather than inference and speculation.

[rob9]

I use a fixed IP address in my Asus router for my hubs.

They appear to accept that from DHCP without a problem. I'm not sure what the issue is in your case.

(a bit of a tip: there are only a handful of people working for Hubitat and they are all on here. They tend to be far more helpful to those with positive attitudes rather than those who personally attack them and their intelligence)

[johnwill1]

[ktd]

@elfege

Hubs that fail DHCP renewals after reboot.

My guess it’s your network setup and/or SonicWall hardware. I have no issues using Unifi, also using ”segmented VLANs, NAT rules”.
If I change the ”fixed IP” on my UDM for my Hubitat and reboot my Hubitat, I get the newly assigned IP emeditly.

[sburke781]

I'm certainly no expert, but a couple of things that may help others help you could be (and apologies if I have missed any mention of these already):

• What platform version are you running?
• Is there any Wi-Fi setup involved at all?
• Do you have a static IP configured on the HE hub (I've possibly got my terminology mixed up there)?
• It could help if you posted some screenshots of the network setup on the HE hub, blocking out any sensitive info

Just some suggestions....

[rlithgow1]

As a network engineer, I have yet to notice a problem on any of my hubs getting DHCP. Just changed my reservation and within seconds the hub just changed. Changed it back, hub changed back to original IP. (I use a Watchguard 35 for DHCP)

[marktheknife]

@elfege

I’ve been using Hubitat for years. You probably remember me from when I was a clueless beginner. Fair. I asked rookie questions. I learned.

But here's the part you seem to have missed: I evolved. You didn’t.

It’s a shame that despite all that personal growth, you apparently didn’t learn anything about how to act like a professional when working with other people.

[aaiyar]

@elfege

Okay, plot twist. Turns out I was looking at the wrong hub.

Thank you for this update. I’m sorry for your colorblindness.

Given that no one is able to reproduce your claims, and that you’ve been let down by your defective vision, I’d suggest you revise/remove your wholly unwarranted rant.

[bptworld]

Okay, just got out of bed... still drinking my first cup of coffee. Let me see, Wow.. Look at all those credentials - not impressed.

Now about the little black box. Hubitat has said time and time again that it's designed for the average user. So let's go over what the average user needs to do...

• Plug box in
• Go through setup
• Once setup in done, go into their routers setup
• In router setup, make the IP address static (every router is different but same concept)
• Done, never worry about IP again - unless router is changed/upgraded

Wow, all that without having all that experience/knowledge! Sometimes people just can't see the forest for the trees.

[Bloodtick_Jones]

OP got throttled harder than hotel WiFi. Next time, add a TTL to your early AM rants.

[aaiyar]

@Bloodtick_Jones

Next time, add a TTL to your early AM rants.

Brilliant .... you gonna clean the coffee off my keyboard?

[lcw731]

@elfege

No diagnostic tools.

ahem

[rlithgow1]

[hydro311]

Every post everywhere that begins with "Marvel in awe at my eminent qualifications, all ye small & weak plebes!" always has this same oh-so-predictable crash-&-burn ending.

As soon as I saw this one posted last night, I figured it would be no different.

[rlithgow1]

Well as someone who has climbed oil coated poles, the use of Vaseline in electronics is recommended after a through washing of a plugged in power supply...