Client IP Conflict

[MarkBrown]

We just refreshed to Meraki at 1 of our sites.

We are seeing multiple alerts for IP conflicts. 

The odd thing is the 2 MAC address are identical on the first 10 digits.

its for our Cisco server on-site with hypervisor.

These devices are statically set. no DHCP scopes are built.

On the Meraki the Vlan for this is set to do not respond to DHCP requests.

I am not a server person. but anyone knows if Cisco uses a virtual NIC behind the physical?

Has anyone seen this issue?

Thanks Mark B

[Bruce]

Not sure of your problem but can confirm that Cisco UCS servers quite often (almost always) use VIC cards, which employ a form of virtualisation where you can split one card into multiple cards that are presented to the server/hypervisor - hence why you’ll only see the last couple of bytes on the MAC change.

As for your address conflicts, does the physical server have multiple network interfaces, and are you running VMs on the server? If so maybe the VM environment isn’t behaving properly… that’s all I can think of.