Duplicate client IP addresses in virtual SmartZone

[JBishopYelm]

Hey Ruckus community,

I'm running into multiple clients with the same IPv4 address in our wireless environment.  We've been digging into this pretty hard and I'm hoping someone has some good recommendations to help us figure this out:

So far, I've seen the IP duplicates in pairs (two devices, one IP address) - this is gathered by exporting ALL wireless clients from our smartzone, sorting by IP and filtering for duplicates.  The results are fairly consistent - we have 15-30 clients with duplicate entries during the business day (out of 2,000-3,000 clients), and they are from two of our WLANs.  A majority of these devices are our managed Windows 11 clients, and a small portion is guest mobile devices/phones.  We have 8-hour DHCP and DNS leases from on-prem DHCP and DNS servers.

In these situations, the 'newer' of the two clients has a valid DHCP lease, but is unable to pass traffic.  The 'older' of the two clients has no DHCP lease, but still appears connected in SmartZone.  While working with support, we've disassociated the 'older' client and service was immediately restored to the 'newer' client.

In the one instance I've managed to get my hands on both devices fighting over an IP, the 'older' device was in hibernation and immediately changed IP addresses/got a new DHCP lease once booted.

Here are some of the things we've looked into:

• DHCP pool sizes, reservations, and static IP addresses - none of these show any signs of problems
• Date/time on affected clients, DHCP server - no signs of issues yet
• MAC addresses of affected clients are unique
• MAC/ARP tables on routers have plenty of room
• Conflict Detection is enabled (2 tries) on DHCP server
• DHCP Dynamic DNS updates enabled
• No load balancers/redundant DHCP servers (no replication)

Sorry for the long post, but hopefully if you've read this far you can throw me some suggestions to look into!