Hi Jason, So currently Unity uses a very similar (if not identical) raid technology to VNX2 (called MC-X - I think there are some whitepapers on support.emc.com discussed MCR/MCC/MCF)  I have heard rumblings of change but am unclear when etc, and obviously future development cannot be discussed publicly etc  So to answer your question - at this stage yes Unity is vulnerable to a double fault in the same rg. Obviously we in engineering have methods to attempt to bring a drive back online etc but a lot depends on what has happened to the drive etc. And needless to say every Unity case is being scrutinized closely  at present.  Hope that helps Gearoid
Hello,  I wanted to start a discussion here because I am a little confused.  We have a VNX5400 array that suffered a double fault on 2 EFD drives in one of the Raid Groups of the Pool.  It appears that recovery of that pool is limited to destruction and recreation.  Does that sound right to all of you?     Seems there are some ways around this.  E.G.  Force drives online like we did 15 years ago,  or allow the EFD drives to go read only to reconstruct the RAID group.   Or perhaps even have a RG able to be removed from a pool.  (aka the opposite of expansion).  I feel like we are missing a technique or ability to recover from this event more cleanly.  What do you think?
What is the best way to recover from a double fault on a VNX array Pool?