C-8 didn’t send any data ERR_EMPTY_RESPONSE

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1

I'm having a strange issue trying to connect to my C-8 Hub.
When I plug it in the hub boots up normally, with the light going from blue to green.
When I search the MAC address on findmyhub it quickly finds the hub and gives me an IP address. When I ping this address from the command line it responds normally.
However, when I click Connect to Hub I get an error page with the message

This page isn’t working
129.xx.xxx.xx didn’t send any data.
ERR_EMPTY_RESPONSE

The same happens when I try to access hubitat.local or the diagnostic tool at 129.xx.xxx.xx:8081

What's strange is that when I first connected the hub several weeks ago it worked fine. Then I had to step away from the project for a couple weeks and now I can't connect.

I've tried rebooting the hub, rebooting the ethernet switch the hub is connected to, rebooting the computer I'm working on, and resetting the hub with the button on the underside, but nothing changes.
I even tried connecting a new hub, fresh out of the box, never been turned on, and I got the exact same behavior.

Any help with this would be much appreciated.

Thanks,
Bryan

2

129.xxx.x.x would be unusual.

Are you sure it isn't supposed to be the more typical 192.xxx.x.x

3

Yes I'm sure. I'm on a work network which could be why it's different.
My computer is connected to the same 129 network.
Hub Search

4

On Registered hub, click details, check when the last checkin is.

image

On the Find Hubs section, try the advanced search using the MAC (on bottom of hub if using ethernet).

5

Is it possible the IP address is causing problems, since he's not using a standard private IP address (e.g., 10, 172, 192).

6

IP should not matter as long as the workstation is in the same subnet as the hub, and access is not being blocked by a firewall.

1 Like
7

I'm not sure how to check the last checkin, since I cant access any sort of UI to communicate with the hub, so there's no details button for me to click.
I used the Advanced search with the MAC address and it finds the hub just fine, that's where I'm getting the IP address. But when I click "Connect to Hub" I get the ERR_EMPTY_RESPONSE page.
I don't think the IP is an issue since I get the exact same behavior when I try to access it with hubitat.local.
I also don't think it's a firewall issue because I was able to connect to it a few weeks ago, and I haven't changed any of my computer settings since then.

8

My Hubitat > Registered Hubs
Nearly the same place I assumed you were getting the IP from.

Run arp -a from command line and find that IP in the list, see if the MAC is correct. You can also look for the MAC and see if its under a different IP. You could have an IP conflict where two devices have the same IP so your http requests may be going to a different device.

9

I just ran arp -a in my command line and the MAC address for that IP does match the MAC address of this hub. Also the MAC address isn't duplicated anywhere so it doesn't look like it's an IP conflict.

10

No clue then. The only other thing I would try would be to take the hub to a more controller environment, like a simple home network. If LED is green that should mean the main platform is running. Not be able to access the diagnostic tool is very suspect. I feel like it is being blocked by the network configuration in some way.