If you are looking to preserve the data and configuration, then no there isn't a way to downgrade the cluster.  Also just to mention it for anyone that might be interested, there isn't any way to roll-back an upgrade either.  Any procedure to downgrade the cluster would be destructive as it basically requires reimaging the nodes.  The easiest way since the cluster is built already would be to upload the image file (.img) then kick off the reimage via the isi_reimage command.  This is the best argument for why you would decide to use isi_reimage over doing so individually via a USB thumb drive.  Then once finished, connect a null modem cable to the serial port of the first node and you'll be presented with the familiar initial setup menu and then you can rebuild the cluster.
Hi, Im trying to downgrade the firmware on my Isilon cluster from 7.0.2.4 to 7.0.2.1. I get the following error  /var/log/upgrade.log   update_engine_2013-10-23_21:34:11.txt 2013-10-23 21:34:13,282 INFO Update engine starts. 2013-10-23 21:34:29,554 INFO Got new version from source: 7.0.2.1 B_7_0_2_123(RELEASE) (0x70002500010007b) 2013-10-23 21:34:29,667 INFO Loading from cluster 2013-10-23 21:34:29,668 INFO Loading image finishes:localhost 2013-10-23 21:34:42,813 WARNING Abort from previous error. Update failed. 2013-10-23 21:34:42,814 INFO Update engine finishes. 2013-10-23 21:34:44,819 DEBUG Executing: /usr/bin/pkill -KILL -g 59736 2013-10-23 21:34:44,826 ERROR /usr/bin/pkill -KILL -g 59736[signaled:1 ]: 2013-10-23 21:34:44,827 ERROR Failed to run:/usr/bin/pkill -KILL -g 59736  First, is it possible to downgrade firmeare? 2nd is there somewhere I can get a more detailed error?  Thanks Jim
Downgrade firmware 7.0.2.4 to 7.0.2.1