I know it is recommended to use DHCP to assign an IP address to eisy and that is how I have my eisy setup. In my network gateway I run a DHCP server and there I added an ip address reservation for eisy. This worked really well up until the upgrade to v6.0.5. Since then the ip address on my eisy changes randomly every 15-20 minutes. Very weird... I would not be a big problem because I can get to the Admin Console using the ioX launcher but it breaks connection on the UD mobile app and Polyglot interface. Yes I can work around it but I have been told by my wife that I need to fix the app because it is currently "unusable" and "useless" as far as she is concerned.

Is eisy changing it MAC address dynamically and that is why the address reservation is failing? Can I just hard-code the ip address? I tried in the admin console under configuration but it will not allow me to unselect the "Automatic" and then set an IP address

It sounds like this would be more of an issue with the router. Especially since you configured a reserved DHCP address. When you look in your router's connected devices, does the eisy's MAC address stay the same, even when the IP address changes?

Is there a chance eisy is switching between wired and wireless or do you have a mesh system where eisy is changing acces points?

Guy said "It sounds like this would be more of an issue with the router. Especially since you configured a reserved DHCP address. When you look in your router's connected devices, does the eisy's MAC address stay the same, even when the IP address changes?"
Initially I thought so but I have about 40 reserved ips and the only one changing is eisy. And I only saw this behavior once I updated to 6.0.5 about 2 months ago.

I have checked the router and at the time it did not show multiple mac addresses

tazman said: "Is there a chance eisy is switching between wired and wireless or do you have a mesh system where eisy is changing acces points?"

It is hard-wired to the main router, so I am not sure if it is switching from wired to wireless but that makes sense. Yes, I do have a mesh network but as i said it is hard wired to the main router so i do not thing it is swithing nodes and it is within 4 ft of the router. I will look further into the switching from wired to wireless. Just not sure why it is doing it now.

3 hours ago, leonpc said:

makes sense. Yes, I do have a mesh network but as i said it is hard wired to the main router so i do not thing it is swithing nodes and it is within 4 ft of the router. I will look further into the switching from wired to wireless. Just not sure why it is doing it now.

If your router has logs I would look there. You might have to raise the log level to see each DHCP address assignment. Wait for it to happen again and go look there.

The answer should be there. The factory MAC address for the EISY should be on it's case for reference.

6 hours ago, leonpc said:

It is hard-wired to the main router, so I am not sure if it is switching from wired to wireless but that makes sense. Yes, I do have a mesh network but as i said it is hard wired to the main router so i do not thing it is swithing nodes and it is within 4 ft of the router. I will look further into the switching from wired to wireless. Just not sure why it is doing it now.

If you ever setup the wifi then it is still in there and it will obtain multiple ip addresses. It used to be you press the multi function button 4 times to reset the wifi. You should be able to see in your router what kind of connection an ip address is using so I think this is going to take some investigation on your end to see exactly what is happening.

16 hours ago, leonpc said:

tazman said: "Is there a chance eisy is switching between wired and wireless or do you have a mesh system where eisy is changing acces points?"

It is hard-wired to the main router, so I am not sure if it is switching from wired to wireless but that makes sense. Yes, I do have a mesh network but as i said it is hard wired to the main router so i do not thing it is swithing nodes and it is within 4 ft of the router. I will look further into the switching from wired to wireless. Just not sure why it is doing it now.

You may want to disable wifi completely.

Open an SSH session, and use this command:

sudo udxops.sh wifi.disable

On 5/31/2026 at 4:10 PM, bmercier said:

You may want to disable wifi completely.

Open an SSH session, and use this command:

sudo udxops.sh wifi.disable

Thank you. I did this and will monitor the system over the next couple of days

Ok... So there is definitely something going with the eisy and it all started after the update to v6.0.5

I have been using the DHCP server on my gateway switch and it worked fine except I ran into a limitation that i could only reserve 64 ip addresses. I figured i could live with that and so did nothing. when this issue with EISY started I started thinking about it again and in essence people higher up in the thread said if address reservation is not working, then it is an issue at the switch. And with the combination of the address roulette and the 64 reservation limitation I decided to pull the trigger and install pi-hole.
Even after setting up pi-hole I could see that eisy is still changing addresses even though the address is reserved. Looking in the log I see DHCPdecline errors from eisy. I checked the network and there were no other systems using the address I was trying to assign

Have you tried reserving a different address than your usual one for the eisy? Those dhcpdecline messages might be a hint that things aren't the way you think they are.

I can try that... At this point I am willing to try almost anything.

Although something interesting I have seen... In pihole when you use the DHCP server it assigns a unique identifier to any of the addresses and try and use that in the futureto speedup assigning addresses. This would take the format of 01:macaddress and when you have multiple network cardsin the same system you may see 02:macaddress:systemid

eisy I see the following:

ff:b9:02:66:f4:00:01:00:01:2f:95:52:e8:macaddress

Edited Monday at 04:01 PM4 days by leonpc

Is it possible you have two dhcp servers on your network? If the mac address is always the same, but the ip address is changing, this has to be a problem with whatever is assigning the ip address. When you see the non-correct ip address getting assigned, is it always the same "other" address, or is it always seemingly something random?

If it was an issue with it switching back and forth between wifi and ethernet, you would get a different mac address for wifi and ethernet, but I would expect it to keep getting the same ip address when on wifi and the same for every time it is on ethernet, even if you don't have static dhcp assigned to both. DHCP servers generally give the same IP address to something over and over unless it has been offline for an extended period of time.

I doubt ISY firmware plays a role in IP address at all. The Eisy/Polisy firmware runs on top of FreeBSD which I am sure is handling all of that.

1 hour ago, apostolakisl said:

Is it possible you have two dhcp servers on your network? If the mac address is always the same, but the ip address is changing, this has to be a problem with whatever is assigning the ip address.

That's also the kind of hypothesis that comes up in my mind. That's why I asked if the MAC address stays the same (though that question wasn't really answered). I just can't see the eisy itself causing this kind of issue.

DHCP addresses are given out as a "lease", which expires and needs to get renewed. If the renewal comes from a different server, this kind of thing could happen at regular intervals.

Looking back at the original post, he says it changes every 20 minutes or so. That is hard to explain. The device (eisy) asks for a lease via a network wide request (the first time), the router hands out an ip with a lease length. Check the router to see what that time is set to, 24 hours is common. The device keeps track of its lease time and it requests an extension at the half way point. At this time, the router could give out a new address (but wouldn't unless you changed settings on the router). Devices usually don't put out a broadcast request for lease renewal, it usually goes directly to the dhcp server IP that gave its current lease, so a second dhcp server shouldn't even know about it. If it asks for a renewal and gets back crickets, it will just keep the current IP address and keep trying. At least this is how I understand it all works.

Anyway, for the ip address to change in 15 minutes, that would imply the lease time was only 30 minutes and that the request for renewal came with a change of IP. I expect that FreeBSD is handling all of this. I don't know how that could get corrupted in such a way to do this weird behavior.

I'm assuming all of the IP addresses that eisy is using are on the correct subnet. Assuming that FreeBSD was going bananas and just giving itself random numbers, they would not all be in the same subnet. IF you telnet into eisy, there are commands to see the status of the dhcp client, you would have to look them up, I don't know them off the top of my head. You can also assign a static IP address via telnet. Again, need to look up the commands.

On 6/7/2026 at 1:57 PM, Guy Lavoie said:

Have you tried reserving a different address than your usual one for the eisy? Those dhcpdecline messages might be a hint that things aren't the way you think they are.

I have tried it can it still has not stopped the address swapping from happening.

I am at the point where I am running wire-shark on my network searching for a rogue DHCP server. I have not been able to identify one at all. Currently the only device that is swapping id addresses is the EISY.

@Michel Kohanim Did you perhaps enable virtual mac addresses with the v6.0.5 update. It is a long shot but I am asking

On 6/9/2026 at 9:53 AM, apostolakisl said:

Is it possible you have two dhcp servers on your network? If the mac address is always the same, but the ip address is changing, this has to be a problem with whatever is assigning the ip address. When you see the non-correct ip address getting assigned, is it always the same "other" address, or is it always seemingly something random?

If it was an issue with it switching back and forth between wifi and ethernet, you would get a different mac address for wifi and ethernet, but I would expect it to keep getting the same ip address when on wifi and the same for every time it is on ethernet, even if you don't have static dhcp assigned to both. DHCP servers generally give the same IP address to something over and over unless it has been offline for an extended period of time.

I doubt ISY firmware plays a role in IP address at all. The Eisy/Polisy firmware runs on top of FreeBSD which I am sure is handling all of that.

As I said in the previous post I have been looking for another DHCP server but have not found one yet... I have another trick up my sleeve to try but so far nothing. It seems to change ip addresses every 3-6 hours. If I notice the new address and I reboot eisy it comes up with the address I expect. I assign addresses for 24 hours at a time, so the 3-6 hour timing puzzles me. Also the secondary address is random but it is always within my allocatable address range. Also the DHCP server reports the address with a lease time as if it provided the lease. There is one other thing... I have mentioned it before, but at the time that the ip address change you can see an interesting transaction in the logs:

1. Lease is still valid

2. EISY request an address

3. DHCP server responds with the reserved address

4. EISY decline the address and request another address

5. DHCP server responds with the reserved address

6. EISY decline again

7. Silence for a few seconds

8. A bunch of ARP requests from EISY

9. Silence again for a few

10. A lease request from EISY containing an address that is free

11. the DHCP server response with a lease for that address

That whole behavior makes me think there is not a second DHCP server but I would rather make sure. At least I have no issue with networking tools but this one is really stumping me.

I don't know why eisy would request a new address and decline to accept the reserved address the dhcp server offers up. As I mentioned before, pretty sure that is all handled by freebsd OS, not ISY application. I would research freebsd network interface configuration and see if you can't overwrite it with default settings. It sounds like something is funky in there.

Well I've been trying stuff on one of my test Polisys (I tell you, they really get used), and I just might have a workaround (not a fix) for you. This could also be a nice hack for those who for whatever reason might want a fixed IP address and can't do it with a DHCP reservation. You gotta be ok with going into your controller with ssh to do this.

FreeBSD allows you to set more than one IP address for a network interface. The idea here is to let DHCP do it's thing, which keeps UDI happy because the correct default gateway, nameserver, etc settings are acquired. Then you define a second IP address that can be static, as an alias. It only takes one line added to the /etc/rc.conf file. The line is (for a eisy) "ifconfig re0 <fixed IP address> netmask <netmask> alias". The terminating "alias" is of utmost importance! For whatever reason it is suggested that the netmask be different than the default one, so I made it smaller. Here is what the line looks like in my /etc/rc.conf file. Note that this is a Polisy, so the network interface is "igb0" instead of "re0". The last several lines a somewhat different on a eisy.

The reserved DHCP IP address for this Polisy is 192.168.0.137, so I made the fixed one 192.168.0.37 to keep it simple. My router's DHCP range is .100 and up.

Now if you look at your network configuration with the ifconfig command, you see both addresses, like this:

I manually added a new entry in IoX Finder to show the new IP address. It looks like two separate controllers, but with the same UUID.

I tested it with admin console, going into PG3, and eisy-ui. All work fine, even after a reboot. An IoX upgrade might delete the added line so you could need to add it back if that happens.

Let me know if you or someone else tries this.