AL1920 losing IP address

5069-310ERM controller Ver31

This new machine we have has 3 IFM AL1920 IO-Link masters in it, all in the project tree in the processor. For reasons unknown, 2 of them like to randomly change their IP addresses.
One went from: 192.168.1.20 to 192.168.1.250.
The other went from: 192.168.1.21 to 0.0.0.0.
This has happened twice now. Set the IP address to what it should be and all is good.

Has anyone seen this with IFM IO-Link master devices?
Can other things in the panel change an IP address?

The panel is connected to a larger plantwide network, but that goes through a 1783-NATR first, and only the PLC is setup in that.

Thanks
Justin

What switch are you using? Some switches have DHCP persistence. Meaning that you can assign an ip address to a port, devices plugged into the port will be assigned the port IP address. It’s a little more in depth than that buts the high level “this could be possible”?

You set the IP but did you set the mode to static? Some devices let you set an IP but if you don't set it to static the setting is ignored.

The switch is an N-Tron 716TX. I am not familiar with the N view software for them, working on that. But they don't seem to be set up to push IP addresses.

The problem devices are set for static addresses also.

Generally.. unless there is some curious setting for Static Unless Collision (which i've never seen) a Static configured device will never change its own address. Consider setting it to dynamic, having it acquire and IP or fail and gain a 169. series address, then switch it back to static and give it the proper address. I have on rare occasion seen devices be set to static, and not be set there internally, as if some leftover bit in the user interface side is effectively lying to the operator.