Clients get IPs but no internet after upgrade. Fix: The 2021 firmware tightened DNS validation. Go to System > General and manually set a DNS server (8.8.8.8) instead of relying on DHCP.
Recommended for stability.
For users managing these devices in 2021, the focus was on maintaining the final stable versions of the 6.5.4.x firmware branch: Aruba Instant 6.5.4.x (Taurus):
You need a valid Aruba support contract and ASP (Aruba Support Portal) account.