I have 3 Ruckus APs (720, 710, 510) connected to a switch, which is connected to a router/DHCP server/DNS server.
When connecting a client device to the WiFi network, there is a short period of time (1 to 2 seconds) immediately after the WiFi connects where the client is unable to reach the network.
The issue only happens immediately after connecting - after those 1-2 seconds, the WiFi on all my devices works great, is rock solid, and blazing fast. And - it only happens on 5G, or at least, this delay is much longer on 5G than 2G. It happens on all 3 APs.
Why does a delay of a few measly seconds matter? It matters because Android uses network unreachability detection (NUD) to determine whether it's connected to a usable network. It does so by sending ARP requests to the default gateway. If NUD discovers the network is unreachable (i.e. no responses to these ARP requests arrive), it terminates the WiFi connection. Sometimes, NUD triggers before this weird problem fixes itself.
As a result, my Android phone sometimes takes 2, 3, or 4 attempts until it successfully connects to my WiFi. This is particularly annoying during roaming, as the wifi drops when walking around the house.
Is someone else observing this behavior? (The issue might also be on the client side, or with the switch, or with the router - but the fact that it is limited to 5G makes me very, very suspicious of the AP: EDIT: Yep, the culprit is the AP/Unleashed. I'm really peeved to find bugs like that in a networking device with a $1200 MSRP.)