Hi, I was confirmed for this matter to Isilon technical support. It was that updating multiple drives at the same time may cause these drives to be unavailable at once thus causing a larger performance impact or even system unstable. So, EMC would recommend upgrade drive firmware node by node.  Best Regards Taro-X
Please let me know how to update drive firmware from DSP(Drive Support Package). Can I update the drive firmware at the same time in plural Node?    drive firmware update command : isi devices -a fwupdate -d   If I can update it at the same time in plural Node, do you have any impact on performance?  Best Regards, Taro-X
How to update drive firmware from DSP