VNX5200 and VNX5300 iSCSI configuration and topology

Hi All,

I am in the process of building a VNX5300 and VNX5200 using 1GB iSCSI connectivity to hosts. Please let me know if the below designs would make sense, I am not 100% certain, as I have not dealt with iSCSI in a while.

In case with 5300 I am using a single switch for iSCSI, which is partitioned into two VLANs with different subnets: VLAN_A - 10.10.10.0 and VLAN_B 10.20.20.0. I know it is not the best practice to have only a single switch, but there is nothing I can do about this - there is only one switch.

Hosts are ESXi 5.5, they have two available 1GB NICs for iSCSI - one will connect to VLAN_A and have the IP of 10.10.10.xxx, the other will connect to VLAN_B and have the IP of 10.20.20.xxx.

VNX5300 will have two quad-port iSCSI IO modules installed. I want to connect two ports from SPA - A4 and A6 to VLAN_A, they will have the IPs in the 10.10.10.xxx range, and two other ports from SPA - A5 and A7 to VLAN_B - they will have the IPs in the 10.20.20.xxx range.

SPB ports will be connected the following way - ports B4 and B6 to VLAN_B - they will have the IPs in the 10.20.20.xxx range, and ports B5 and B7 to VLAN_A - they will have the IPs in the 10.10.10.xxx range.

The hosts will have two iSCSI vSwitches configured - one for VLAN_A and one for VLAN_B, and will have iSCSI kernel IPs configured as mentioned before - VLAN_A 10.10.10.xxx, and VLAN_B 10.20.20.xxx. Under the iSCSI Software Initiator Dynamic Discovery tab I will specify the VNX target ports - 4 IPs from SPA and 4 from SPB (not quite sure about this though, I think for Dynamic discovery I might need to specify only one from each SP - VLAN_A and VLAN_B, and the ESXi will discover the rest).

In case of VNX5200 it is a bit more complicated - I need to connect it to the existing hyper-v hosts that are connected to the previous gen VNX via iSCSI using two separate switches, lets call them switch1 - 172.16.10.0 and switch2 - 172.16.20.0.

I was thinking of utilizing the same host iSCSI NICs to connect to the new VNX5200, only for the purpose of moving the data from the older VNX.

I will connect the new VNX5200 to the switches the following way: two ports from SPA - A4 and A6 to switch1 and and two other ports from SPA - A5 and A7 to switch2, ports B4 and B6 to switch2, and ports B5 and B7 to switch1.

Then I will set up the target iSCSI IP addresses on the VNX5200 ports that will be in the same subnet(s) as the existing array (8 IPs total, one for each connected VNX5200 iSCSI port) - SPA - A4 and A6 and SPB - B5 and B7 - 172.16.10.xxx, SPA - A5 and A7 and SPB B4 and B6 - 172.16.20.xxx. Then I'll use Unisphere Server Utility on the hosts to connect to the new VNX5200, then present the LUNs. In this case I think the servers will have access to both arrays at the same time, and the VMs can be moved to the new storage. Once that is done, the older array can be disconnected.

Please let me know if this makes sense. Appreciate your input.