01-25-2019 11:20 AM
Have found this thread after frustratingly experiencing a similar issue. I have 1 device which gets this ip4 address whenever my UniFi Switch is restarted (firmware upgrade, temp power loss, etc); unfortunately, it's my alarm system panel, a Honeywell Lyric which is WiFi only and I cannot static assign it an address directly on the device. I only have Ubiquity network gear and a few dumb TP-Link switches, EdgeRouter(1)->UniFi Switch(1)->UniFi AP-AC-Pro(4)->Lyric(1). No USG gateway. I have 2 LANs defined on the router, 192.168.1.x and 192.168.4.x (guest/IoT) as a VLAN of 1001 with the router providing DHCP services authoritatively for both networks. The WAPs have 2 SSIDs for each LAN and I've firewalled the 4.x LAN from being able to connect to the 1.x LAN, but allow the opposite to connect for management purposes. I've configured the 4.x clients to flow through port 1 on the Switch which is configured for the 1001 VLAN profile and a different port for the 1.x LAN profile. I've also configured the UniFi Controller settings for the LANs with DHCP guarding referencing the corresponding router addresses just in case I had a rogue. All my other 4.x and 1.x clients work just perfectly as expected except for this singular device which I'd simply replace if I could, but it's a rather significant investment and I like it alot otherwise. When I configure this client to join the LAN SSID, it joins to it just fine and gets the reserved router's DHCP address in the 1.x network and it stays connected for weeks. If I have a power outage or update the switch's firmware, then within a minute or so, it reverts to 169.254.9.104 address; so, somehow it can't find the DHCP server which I don't understand how not; this doesn't happen when the router is restarted, just the switch which I discovered today while updating the WAP/Switch firmware to the latest version. I can recreate this at-will by simply restarting the switch. I know this is difficult to diagnose this way, but am appreciative to any experts out there that can point me in the right direction; thanks in advance!