Cisco WLC – Upgrade FUS image
Today I upgraded a FUS image on a Cisco WLC 5500 controller, because I also upgrade the WLC software to 7.2.103.0. The FUS upgrade is straightforward and comparable to a regular software update. The only difference is that you need console access to perform the upgrade. The FUS image upgrades the following components:
- Field Recovery Image is upgraded to runtime image version
- Bootloader is upgraded to 1.0.16
- Offline Field Diagnostics is upgraded to 0.9.28
- FPGA Revision version is upgraded to 1.7
- Environment Controller (MCU) Image version is upgraded to 1.8
- USB Console Revision version is upgraded to 2.2
During the upgrade process you have to confirm to proceed the upgrade, like shown below
Checking for Field recovery image upgrade
Field Recovery Image upgrade …
Upgrade Field Recovery Image from version 6.0.182.0 to 7.0.112.21
Are you sure you want to proceed (y/N) ? y
******************************************************************
* Please make sure POWER SUPPLY is always ON during this period. * ******************************************************************Erasing Flash (estimated 49 seconds) …
Writing to flash (estimated 716 seconds) …
This happens multiple times and the controller reboots several times during the upgrade. It took about 20 minutes for the complete upgrade of the FUS image.
René Jorissen
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Hi! Do you know if, when theres the FUS update, the users can still use the antennas?
Or the wifi goes down?
thanks!
Dear Xavier,
The wireless environment will be unavailable, because the controller is not operational. Ofcourse this is not true when you are using a redundant controller.