We have a ticket open with EMC on this. The VNXe SP failovers work nothing like the Clariions.  On a Clariion with redundant SPs and multipathing, you'll have four active paths all the time (both SPs going to both switches). On a VNXe, you'll have only two paths active (the SP that "owns" the Storage Repository/Datastore going to both switches).  On the VNXe, each SP listens only for its own IP addresses. When an SP fails, the remaining SP will have traffic rerouted to it via an internal bus and will also start responding to requests to the IP addresses of the failed SP.  This failover process based on our testing can take as little as 37 seconds, or as much as a minute and a half.  Consequently, EMC have formally advised us to set the High Availability timeout on XenServer pools to 120 seconds, to prevent XenServer hosts from self-fencing during an SP failover. The default HA timeout on XenServer is 30 seconds. FWIW, until our ticket was escalated, EMC Support told us the failover would "always" take less than 30 seconds to complete.  Different guests will of course respond differently to having their iSCSI storage denied to them for more than 30 seconds. We have found that most will crash and reboot.  Fortunately, the reboot process takes longer than the SP failover does, so the storage is avialable for the rebooted guests to use -- especially when the rebooted guests take some time to run fsck or chkdsk and clean up those inodes orphaned by the way too long SP failover.  YMMV.  Mark
Dear all,  today we wanted to test if the failover is working correctly and if in case of failover the vmware datastores still provide functionality to keep the VMs running.  Our vnxe3100  ( 2.1.3.16008 ) dual sp is serving 2 esxi5 hosts Our esxi5 hosts (2 DL380G7) are connected to two dedicated iscsi switches  which are connected to the SP A and SP B of the vnxe.   Trying the failover we expected that the datastores would still be available in vsphere and that the VMs continued to run without crashing.  BUT: during the failover process for a brief delay of  2-3secs vsphere showed the datastore as non accessible and one of the 3 testing VMs crashed while the other 2 kept running.   Have you tried the failover process ? Is this behavor normal or should we expect a more responsive failover ?   Is there any configuration to tune ?  Thank you for your feedback
slow iscsi failover