The firmware upgrade process consists of making a change in the image that runs in the SBC for a more updated version.
Each update published by the manufacturer contains improvements and a bugfix over previous versions, which means avoiding possible problems in the operation of the service.
In the case of clusters in HA, the firmware update would not entail a service outage, as it acts on the equipment in standby in the first instance, switching the service and repeating the process on the other equipment in the standby role after switching.
The process to follow for this task would be:
Preliminary tasks:
1. Verification of the current FW version of the equipment
2. Download of the new firmware version, verification of the release notes and upload of the new version by FTP to the SBCs in the corresponding partition
Execution of the update:
1. Substitution of the old bootloader file for the new one downloaded, renaming it accordingly in each of the SBCs
2. Modification of the bootparams of the SBCs so that when they reboot they start with the new version of FW
3. Reboot
4. After finishing the update in the standby SBC, balance the traffic and repeat the process in the other equipment.
Rollback
1. Restore the bootparams valueOrderly
2.reboot of the computers
The estimated time for the update process is approximately 1 hour (time conditioned by the upload speed of the new firmware that allows the connection)