Environment
Forti AP U431F – WiFi 6/AX enabled access points
FortiGate Firewall is used as Wireless Controller to upgrade the firmware for Forti AP
FortiGate Firewall and Forti AP are on different VLAN/Networks
DHCP Option 138 is configured on Windows Server 2022 to point to the FortiGate (Wireless Controller) address
Issue
PU431Fxxxxxxxxxxx login:
Upgrading: ............................................................................................................................................................................................................................................................
*OK*
**ret=0
*** Fail to write the image. (written 66296310 bytes, 253 blocks with size 262144)
Sent SIGTERM to all processes
Sent SIGKILL to all processes
Requesting system reboot
PU431Fxxxxxxxxx# print_boot
meru default image status:
len 0x2640014, crc 0x0
AP version is 0.0.0
image status: New image
image try count is 0
fortinet default image status:
len 0x2e00014, crc 0xb37aef52
AP version is 6.2.dc
image status: New image
image try count is 0
fortinet primary image status:
len 0x2a3b290, crc 0xd4eb84db
AP version is 6.2.133
image status: BAD image
image try count is 1
Image ID :fortinet default image
Previous Image ID :fortinet primary image
Auto-learning : Turn ON
Solution
Go to the FortiGate Firewall CLI and remove the WTP images and it is triggering the reboot loop: Forti AP will try to upgrade the firmware from FortiGate Firewall once the WTP image on the firewall is newer than the running firmware.
FW01-ICTFella # exec wireless-controller list-wtp-image
WTP Images on AC:
ImageName ImageSize(B) ImageInfo ImageMTime
PU431F-v6.2-build0307-IMG.wtp 66198789 PU431F-v6.2-build0307 Wed Oct 5 15:46:39 2022
FW01-ICTFella #
FW01-ICTFella #
FW01-ICTFella #
FW01-ICTFella # exec wireless-controller delete-wtp-image
<all>|<image-name> Delete all images or specific image.
FW01-ICTFella # exec wireless-controller delete-wtp-image all
This operation will remove all specified WTP images!
Do you want to continue? (y/n)y
Removing PU431F-v6.2-build0307-IMG.wtp ...
Successful!
FW01-ICTFella # exec wireless-controller list-wtp-image
There is no WTP Images stored on the AC.
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Correct upgrade path for Forti AP U431F and U433F
Please refer to the Forti AP release note for firmware upgrade, the Forti AP U431F has a special requirement for firmware upgrade, particularly with firmware version 6.2.2, you will notice 2 firmware available in the Firmware download portal
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The correct firmware upgrade path for Forti AP 431F and 433F is as below, jumping across versions for this model with end with “rebooting loops”
- 6.2.1 GA build 0237
- 6.2.2 Build 4001
- 6.2.2 Build 0267
- 6.2.3 Build 0281
- 6.2.4 Build 0307
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