The ADVANCED > Firmware Update page allows you to manually update the firmware version of the system or revert to a previous version. The only time you should revert back to an old firmware version is if you recently downloaded a new version that is causing unexpected problems. In this case, call Barracuda Networks Technical Support before reverting back to a previous firmware version.
If you have the latest firmware version already installed, the Download Now button is disabled.
If you have two Barracuda Load Balancers configured in High Availability mode, update the firmware on the passive Barracuda Load Balancer first, then update the firmware on the active Barracuda Load Balancer. The passive Barracuda Load Balancer becomes operational when the active system is rebooted, thus maintaining availability.
If your Barracuda Load Balancers are not in High Availability mode, applying a new firmware version results in a temporary loss of service. For this reason, you should apply new firmware versions during non-busy hours.