MR44 and apple device arp update

[Berty]

Hello, I performed several wired packet captures to compare the behavior between an Android phone and an iPhone on the Meraki MR44 network. We can see that gratuitous ARP requests are correctly relayed by the access point to advertise the Android device’s MAC/IP association to the router, but we do not observe these requests when the device is an iPhone. As a result, the ARP table on the core network does not update, and the iPhone’s connectivity is affected on certain access points. Is there a Meraki fix or workaround available to address this issue?

MR44 firmware 31.1.8 device iphone/ipad version ios 17, 18,26 . Fixed private Wi-Fi, renewable or disabled, no improvement.

SSID in bridge mode / no layer isolation / external dhcp / bonjour disabled

0 problem with windows and android device

[alemabrahao]

This doesn't seem to be a problem on Meraki. Have you contacted Apple support?

You can also open a support case with Meraki.

[Berty]

Hello,
Yes, I have already opened a ticket with Meraki.
What seems strange to me is that the behavior varies depending on the context.

We are observing several clearly different behaviors.

When connecting to a Meraki access point for the first time, the gratuitous ARP is correctly sent and the core network updates its table.
The iPhone therefore does what is needed to announce itself to the network.

However, when moving between access points on the same floor but connected to different switch stacks, the gratuitous ARP requests are no longer relayed.
As long as we stay connected to the Wi-Fi network and the ARP table on the core network has not been cleared, everything works fine across the entire Wi-Fi network.

After a period of inactivity, the ARP table on the core network is cleared, and that’s when the problems start.
When coming back from this inactive period and reconnecting to the usual access point, there is no connection issue.
But when walking around the floor and connecting to access points connected to different switches — while still being close enough for the APs to “see” each other — a connection problem occurs.

I believe that in this configuration, the access points exchange ARP information with each other because they can see one another over the Wi-Fi network, and they do not contact the core network to update its ARP table; they only transfer the session.

[alemabrahao]

When APs are on different L2 segments or connected to different upstream switches, the AP-to-AP sync doesn’t trigger an ARP refresh on the core. The upstream device still has the old ARP entry pointing to the previous switch port.

Once the ARP entry expires, the upstream router expects a new ARP request or gratuitous ARP. iOS doesn’t send one during roaming, and Meraki doesn’t inject it, so connectivity breaks until something forces an update.

Android tends to send gratuitous ARP more aggressively after DHCP renewals and roaming, so the upstream ARP table refreshes automatically.

If APs are in different VLANs or trunks, ensure VLAN tagging is consistent. Misalignment can prevent ARP propagation.

[Berty]

The access points are in the same VLAN and are correctly tagged.
“Android tends to send gratuitous ARP requests more frequently after DHCP renewals and during roaming, which allows the ARP table to be refreshed automatically upstream.”
Indeed, with Android I have observed that there is no issue.
However, since Meraki acts as a proxy ARP, shouldn’t it compensate for this lack of reactivity in order to ensure service continuity for all devices on the market — especially given that Apple devices are very common in enterprise environments and Meraki is primarily designed for enterprise use?
thanks you

[alemabrahao]

Meraki does implement proxy ARP for certain modes (e.g., NAT mode, isolation scenarios), but in bridge mode, the AP typically forwards ARP packets without generating them on behalf of clients. This design assumes that the upstream L2 domain remains consistent during roaming, which isn’t always true in multi-switch environments like yours.

SSID Modes for Client IP Assignment - Cisco Meraki Documentation

[Berty]

I assume I'm not the only Meraki/Apple user in bridge mode with multiple Layer 2 switches. Is there specific documentation for implementing a stable environment for Apple devices in bridge mode with a Meraki Wi-Fi infrastructure?
Do we need to use a specific configuration for Apple devices in a Meraki environment, such as NAT mode, to ensure proper Wi-Fi functionality with Apple devices? Thank you very much.

[alemabrahao]

https://documentation.meraki.com/Platform_Management/Dashboard_Administration/Design_and_Configure/A...

https://www.cisco.com/c/en/us/products/collateral/wireless/access-points/enterprise-best-practices-i...

https://support.apple.com/en-us/102766

[BlakeRichardson]

What is providing DHCP to the clients on the network?

[Berty]

hello the core network.