Catalyst 9120 sends ARP for itself every 5 seconds

[train00wreck]

Hi, i recently received a Catalyst 9120 access point, running in EWC mode with firmware version 17.9.5. I currently have a single SSID configured on it. It is working fine, I am about to add more SSIDs and VLANs. One thing I noticed is that it seems to be sending out ARP requests for its own address, exactly once every 5 seconds. Why is this, and how could i disable it if it's not necessary? I have posted a tcpdump showing the messages below. Thanks for any responses

12:40:13.218851 ARP, Request who-has 172.16.16.62 tell 172.16.16.62, length 46

12:40:13.218851 ARP, Reply 172.16.16.62 is-at 00:00:5e:00:01:01, length 46

12:40:18.218845 ARP, Request who-has 172.16.16.62 tell 172.16.16.62, length 46

12:40:18.218846 ARP, Reply 172.16.16.62 is-at 00:00:5e:00:01:01, length 46

12:40:23.218780 ARP, Request who-has 172.16.16.62 tell 172.16.16.62, length 46

12:40:23.218780 ARP, Reply 172.16.16.62 is-at 00:00:5e:00:01:01, length 46

12:40:28.218692 ARP, Request who-has 172.16.16.62 tell 172.16.16.62, length 46

12:40:28.218692 ARP, Reply 172.16.16.62 is-at 00:00:5e:00:01:01, length 46

[Leo Laohoo]

Please try 17.12.3.

[train00wreck]

I upgraded to 17.12.3 but it made no difference. I even did a full factory reset before the upgrade, and with a default configuration the constant ARPs are still there.

[Rich R]

I think you'll find that is standard behaviour.  The EWC runs VRRP for WLC redundancy and I suspect it is using gratuitous ARP to keep the VRRP address/MAC updated in all APs and switches ARP and MAC tables.

The MAC address you see there (00:00:5e:00:01:01) is the VRRP MAC address.