Gidday Didi
I have LUN 0 showing as the chassis of the MSA2040 as well. The trick to preventing it clashing with storage LUNs is to use explicit mapping for the volumes and start the numbering from 1, that way 0 is unused as the SAN uses it for the controllers.
A few tricks when using the MSA2040 with VMware, first is be sure you set the system "Missing LUN Response" option to use its Illegal Request setting to prevent it skipping some LUNs.
Be sure to shutdown the host server first. Then log into either the controller A or B SMU. In the View panel, right-click the system and select
Configuration > Advanced Settings > Cache and change the LUN response from NOT READY to ILLEGAL REQUEST then click Apply and Restart the host.
Next make sure ALL LUN's are set to use Round Robin Path Policy, but you also need to change the default setting of 1000 message queue depth to just 1 (one) instead of 1,000. that requires an esxcli command and can't be done via the WebClient..
If you have one or 2 LUN's use the command
esxcli nmp round robin setconfig --type “iops” --iops 1 --device naa.xxxxxxxxx
If you have a number of LUN's, you can use the script
for i in `ls /vmfs/devices/disks/ | grep naa.600` ; do esxcli nmp roundrobin setconfig --type “iops” --iops=1--device $i; done
The (I/O) next to an Active means that path is the one that has ownership of the LUN, and the other without the (I/O) is the standby redundant backup. If you lose the current path that has (I/O) on it, the other one will show (I/O) instead as it takes over access of the LUN.
If you read HP best practices, you should not have have all iSCSI ports set to 192.168.254.x but rather pairs A1, B1, A3 and B3 set to say 192.168.254.x and pairs A2, B2, A4 and B4 set to 192.168.253.x so for your example
iSCSI Port 1 with IP 192.168.253.215 (2nd HP DL380p Gen8) is connected to iSCSI Port A2 with IP 192.168.253.115 (Controller A of MSA2040)
iSCSI Port 2 with IP 192.168.253.216 (2nd HP DL380p Gen9) is connected to iSCSI Port B2 with IP 192.168.253.116 (Controller B of MSA2040).
If you want to take advantage of Jumbo frames, enable the tickbox in the host interface settings of the MSA2040 and in the VMware adapter settings, change the "MTU" = 9,000. Be sure to do it to ALL ports though.