Home > Storage > PowerScale (Isilon) > Product Documentation > Management and Migration > Dell PowerScale: Non-Disruptive Upgrade Best Practices > Least Disruptive Firmware Upgrade Recommendation
This option is to upgrade one PowerScale node at a time, which causes the lowest impact on availability and performance during the firmware upgrade process. It has no difference with the firmware upgrade mechanism before OneFS 8.2, which will take a long time for a large PowerScale cluster. The following command is used for this option:
isi upgrade cluster firmware start