iPhone fail to wake up and reconnect

[rhbirkelund]

Over a very long period of time, I've been noticing some different performance regarding iOS devices (me and wifeys iPhones) and my Meraki stack at home.

I often notice that after the iPhone has been "at sleep" for some time, and then open, it doesn't really reconnect. It is still associated to the SSID, as per the icon at the top, but I can't get any traffic through, and fails pings using Fing.

Not until I disable WiFi and enable it again, traffic again flows over WiFi.

The implication of this is that the iPhone looses connectivity to different streaming devices (my glorious Chromecast Audio).

Now I realize that iPhone, will disable it's NIC to conserve energy (Power Save Mode).

As soon as this occurred, I grabbed my Mac and took a packettrace on the channel with Airtool (v1.9.1).

Here comes the interesting part; in the trace I can see the air being flooded with Null Frames, which I can see stems from my iPhone. It's was as if it's informing my AP - continously - that it is going to sleep, and not getting a reply. 1 send, 6 retries; Send and two first retries at 6 Mbps rate, and the rest at 12 Mbps TX rate.

I'm wondering if anyone else has noticed this? I can't really decide if this is a bug or a feature, Apple or Meraki related.

Any feedback would be appreciated.

I've uploaded the .pcap here.

At the time of the packetdump, my Macbook and iPhone, was placed right next to eachother. So the packets received in the trace, should (sort of) reflect the same with regards to the iPhone.

Details;

iPhone MAC: f0:98:9d:c4:c2:2b / Apple_c4:c2:2b

Meraki AP: 32:56:ee:a0:51:a0

SSID: Winona Router

Security: WPA3-SAE Transition (WPA2+WPA3)

RRM: 5GHz only, Minimum bitrate 12 Mbps

At around packet 600 is where (I think), I disable and re-enable my iPhone NIC.

[rhbirkelund]

I'm still curious as to if anyone else has noticed the same.

[BrandonS]

I’ve been using full stack Meraki at my home with sever Apple devices for at least 4 years. The only issues I can recall are one that was pretty specific to packet loss using the RingCentral app and I have on rare occasion grabbed my phone and seen it appear to “catch up” on notifications from the last hour or so. That only happened a few times and it might been an expected result if a device being in low power mode. 

maybe your issue is around WPA3? 

[rhbirkelund]

@BrandonS, I have honestly been wondering the same, if it was related to WPA3.

[Felippe]

I have a similar problem. I use several iPhones, an iPad and 2 MacBooks. For several months now the iPhones, iPad and sometimes the Mac's have been losing connection to the Wifi network. On the device it shows as active, but you can neither ping the device nor does the device have an internet connection. The only thing that helps is turning the WiFI off and on.
In the Dashboard, this is visible under WLAN in the Health tab as a failure. The attached screenshot shows what this looks like.
Unfortunately Meraki support is unable to deal with this. The only advice I got was to change the encryption from WPA3 to WPA2. I additionally use 802.11r adaptive as well.

[paul_richardson]

I do notice the same thing, but only when running MR 26.x or MR 27.x

When I downgrade to MR 25.13 the issue goes away

Haven't got around to doing any troubleshooting, I last tried MR 27.6 a few weeks ago, issues came back, so rolled back to MR 25.13 issue goes away.

[Felippe]

But 25.13 is quite old. It’s disappointing the wpa3 it’s also not working properly. On older firmware I also don’t have this issues.

Besides on Aruba or Extreme Networks I didn’t notice that kind of problems.

[JSalmond]

@rhbirkelund did you get this issue resolved. I am also having issues with some iPads experiencing the the same issue.  when the iPad is woken it still shows the Wi-Fi connection icon, still has it IP address in network details but displays No Internet Connection. Like you we are unable to ping to or from the device. 

Not sure if this is the same as you ? but from our troubleshooting so far we have observed the following 

• Within the dashboard the ipad shows as disconnected, also within client timeline we see "802.11 REASON (CODE 34) Missing Acknowledgements" error  ? 
• Problem is present on our MR33 and MR42 but not on MR36's 
• occurs on SSID's using 802.1x with Cisco ISE 2.7 patch 4 as the Radius server, doesn't occur on SSID using PSK. We are also using CoA to apply Group Policies, however still to test 802.1x without COA to narrow this down. 
• Occurs on multiple iPadOS versions including 14.7.X, 14.8, 15.0.2

[rhbirkelund]

No, I haven't. But then again, I haven't noticed it lately, as things have gotten upgraded since (MBP, iPhone, Meraki).

But in my scenario it was on an SSID with PSK. I haven't noticed it on a wireless network with 802.1x.