Hello,   I'm sorry but no, there's no way to disable that feature.  It was designed into the 7500.    Regards,   Don 
I have a pair of Dell FS7500 I have just setup and the performance is terrible. I have them connected to a Dell equallogic P6110E SAN and everything is great except the fact that I don't have the BPS (UPS) device in use because I have whole building redundant UPS systems that are way better than the little rack mount UPS system the 7500 uses. I don't want to use those little UPS units but if I disconnect them the FS7500 goes into journaling mode and is at least 50% slower than it should be.  Can I force mirroring mode on without connecting a UPS/BPS? I tried on the ssh command line with the file system set normal option. That doesn't help. This seems to be an internally controlled feature of the system.  Thanks 
FS7500 Force Mirroring mode without UPS/BPS