You are correct. In your example, if SPA is unavailable (such as a reboot, or is placed into Service Mode, etc.) then NAS Server A will fail over to SPB, meaning IP_A will be serviced by SPB's LACP Group through switchB ports.  Also, the VNXe3200 does not have FSN. So if a network port on SPA were to lose connectivity, the LACP group would be able to continue servicing data on SPA without interruption. If your NAS Server only had a single SP Ethernet port associated with it and that Ethernet port lost network connectivity, there would not be a fail over of the NAS Server to the peer SP, meaning your clients would be unable to access their data while the network connectivity is down.
Hello,          I read white papers and it is still not clear how the failover works. Any comments would be appreciated.   In below , if SPA fails over to SPB, we get  2 IP's (IP_A and IP_B) on Switch B LACP group 2 ? Am I correct?   Since VNXe 3200 there NO FSN. We do not have cross-stack LACP. NAS Server A - IP_A NAS Server B - IP_B  NAS Server A - VLANA - LACP Group 1 -> SPA port 2 -> switchA port 1  NAS Server A - VLANA - LACP Group 1 -> SPA port 3 -> switchA port 2   NAS Server B - VLANA - LACP Group 2 -> SPB port 2 -> switchB port 1  NAS Server B - VLANA - LACP Group 2 -> SPB port 3 -> switchB port 2
VNXe 3200 SP failover- Network Connectivity - CIFS/NFS