I believe static IP won't save for me because of this "third octet must match" constraint. I'm curious as to why the constraint. Many corporate networks including mine with 100's of vlans uses a gateway with a different third octet.
Hi,
Looking at the note at the bottom, which says that the subnet mask is fixed as 255.255.255.0, this would dictate the host range of the IP address to be 1-254.
If the mask was 255.255.254.0 that would dicate a host range of x.1 to x+1.254.
So you're fixed to a /24 network according to the note about the subnet mask.
Hope this helps
Patrick
Yes, many corporate network support larger subnets. Hubitat is geared towards home use, which rarely has more than /24 subnets.
Is what it is. If you have the capability of making hundreds of vlans, you can make one that is /24 I guess too...
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typically even if using VLANs, the X.X.X.1 address is reserved for the gateway for that VLAN, so even if you put a static IP on a separate VLAN, your gateway for that device would be in the same subnet. i have multiple VLANs in my environment and had no issues putting a static IP on my HE
Well.... I wouldn't say that / not always... Actually I rarely see x.x.x.1 as the gateway address in many of my work and/or industrial networks.
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if you want to haVE a different 3rd octet for your gateway change your subnet mask to 255.255.0.0
You can't change the subnet on the hubitat side though.
did not notice that thanks.. so what if your home is a class b instead of a class c.. i guess you would have to create a smaller subnet just for the hubitat and any wifi devices, and add some static routes to the upstream router so devices on the larger subnet could reach the hubitat.
Yup
So this is for static assigning ??? Anyone have a /23 255.255.254.0 or larger network where it DHCPs the address and honors the subnet mask it gets from the server?
( If I had a spare hub sitting around I would test it out but don't want to mess with my main unit )
Yes, I have a larger subnet (/16) that is working fine with DHCP which makes the mandatory /24 static one a bit perplexing.
Interesting but I can't help ask why you would need a subnet that big? Broadcast storms are still a consideration.
I have 4 vlans, one for home, one for iot, one for guest wifi and one for management. My largest subnet is a /25 and I only give out a maximum of 64 DHCP addresses.
I'm certainly not lauding my own setup but it's Interesting to understand what other people do.
Because this is a home network (versus enterprise) and I have the same number of devices on the /16 that I would have on a /24 so I'm not worried about broadcast storms. I do like breaking things up numerically along the third octet though. I haven't felt the need to worry about VLANs yet.
Besides, previously explaining VLANs and VLSM to my family did not receive the rave reviews I expected.
YMMV
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Funny.
Yeah, I think I've just had it drilled into me. 'Must not waste IP space.' I probably go a bit overboard but I will always keep my iot and guest networks away from my computers and NAS.
I was considering sticking a voucher scheme on my guest vlan, just because I can, but it might have upset the inlaws.
Is RFC1918 ("Private-Use") space really considered "IP space", though? 
I'm attempting to use:
IP: 10.101.9.231
GW: 10.101.254.254
DNS: 8.8.8.8
I believe Hubitat is upset and refuses to use static IP because of the vlan's 255.255.0.0 mask. No matter what I do, DHCP is used and Static is ignored.
What's odd is, it is having zero problems with DHCP on the designated DHCP vlan which also has the same mask above.
Correct.
As it literally says right on the static ip config page:
Subnet mask is fixed at 255.255.255.0
Maybe that will change in the future, but for now that's how it is.
You will have to stick to DHCP if you want a wider subnet.
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Indeed, and understood from the get go. Since DHCP is A-OK with the unique mask, I suspect an enhancement to the Static Networking page should be the sauce in the future. Looking forward to it.
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