Technical Tip: Wi-Fi Users do not get a DHCP IP address when connected to Wi-Fi 6-enabled FortiAP

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Description	This article describes a known issue that users might encounter while connecting to Wi-Fi 6 (802.11ax) enabled FortiAPs.
Scope	FortiAPs with support for Wi-Fi 6/802.11ax (see: FortiAP Wi-Fi 6 Standard and UTP Access Points).
Solution	Known Issue #923964 impacts the wireless clients attempting to connect to wireless SSIDs broadcasted from Wi-Fi 6 (802.11AX) enabled FortiAPs. The problem occurs when a wireless client connects to the SSID and attempts to request an IP address via DHCP. During the DHCP process, the FortiAP transmits the DHCP Offer to the user, but the user fails to acknowledge this packet, therefore it cannot reply with a DHCP Request message; then it times out and finally retries the whole DHCP process. On reassociations, the AP receives a DHCP Request and replies to it with a DHCP Acknowledge but the client cannot process this packet either. This results in the user getting an APIPA address (169.254.x.x) instead of the correct DHCP IP address. A fix for this issue will be delivered in the upcoming FortiAP firmware v v7.2.6, v7.4.4 and v7.6.1. Check first that all configurations on the switch port are correct and upgrade the FortiAPs to the latest available version. Workaround: As a potential workaround, disable BSS coloring first: Disable partial bss color under VAP: config wireless-controller vap     edit "vap-name"         set bss-color-partial disable end Set the BSS color to static. FG # config wireless-controller wtp-profile FG (wtp-profile) # edit 431F FG (431F) # config radio-2 FG (radio-2) # set bss-color-mode static FG (radio-2) # set bss-color 10 As a last resort alternative try disabling 802.11AX on the SSID in the FortiAP profile. To disable 802.11AX, navigate to WiFi & Switch Controller -> Operation Profiles. Select the FortiAP profile then remove 802.11ax in the band configuration. Always engage the Fortinet TAC representative first to ensure matching this behavior.