Proper configuration of Windows iSCSI initiator and MPIO for MD3000i

First SAN 101: you can only share disks if you have some kind of disk locking mechanism in place, like clustering software.

In other words; if you value your data, you don't share disks between servers from a SAN (any SAN).

If you want multiple servers to write to a single (SAN or other type of) disk, give that disk to 1 server and have it share it out to the other servers.

Windows native MPIO is just a framework. The SAN vendor can provide a driver (called a Device Specific Module (DSM) by this framework) that can leverage that framework. The driver for the MD3000i is installed from the Resource CD that's available for download from Dell's support site. The host part is what installs this driver. The Management part is just the management software (to manage the SAN). The "typical" option in the installer installs both the host and management software.

For the IP scheme, you need to isolate the iSCSI traffic from your LAN traffic. This isolation means you also need to use subnets that you aren't using in your LAN.

The factory defaults are:

Controller 0 iSCSI port 0: 192.168.130.101

Controller 0 iSCSI port 1: 192.168.131.101

Controller 1 iSCSI port 0: 192.168.130.102

Controller 1 iSCSI port 1: 192.168.131.102

You can use different subnets, but for each subnet you only want to have a single port on a given controller on that subnet.

As an example, if your server uses 2 NICs for iSCSI and you have assigned them 192.168.130.50 and 192.168.131.50, the iSCSI connection that you need to make (using the "advanced" option in the logon section of the target tab in the iSCSI initiator) are:

192.168.130.50 -> 192.168.130.101

192.168.130.50 -> 192.168.130.102

192.168.131.50 -> 192.168.131.101

192.168.131.50 -> 192.168.131.102

Hopefully this helps some in getting use out of your SAN.

You may also want to read the online documentation for the MD3000i:

<ADMIN NOTE: Broken link has been removed from this post by Dell>

Thank you for the prompt and thorough response Dev Mgr. I admit to being new to iSCSI SAN configuration; though I have worked with Dell and VMWare technical staff to setup and maintain a few MD3xxxi SANs for use with VMWare vSphere ESXi 4.x.

This is the first time I have attempted to access an MD3xxxi SAN using the Microsoft iSCSI initiator from within Windows 2008 Server.

I do have the iSCSI traffic isolated on a VLAN and kept the default port address assignments on each controller of the MD3000i. I also have (2) nics dedicated to iSCSI traffic on the host system, each with an ip address on one of the (2) subnets for the MD3000i (Example: NIC1 = 192.168.130.110, NIC2 = 192.168.131.110).

What I have not done on the iSCSI connection is make more than one connection per NIC. On Each NIC I am currently connecting to 192.130.101 and 192.168.131.101 respectively; there is not a connection to .102 on each subnet. That would explain the inability to initialize the LUN that was assigned to Controller 1 as preferred path on the MD3000i.

I was uncertain if I needed to install additional components from DELL or not; you have clarified that issue for me. Thank you. No such additional software is required with VMWare ... that I am aware of ...

What I find most troubling is your statement that, without clustering or some third party software, I cannot share LUNS among multiple hosts. This concerns me because we have been running our MD3220i for over a year with (2) VM hosts accessing the same LUNS mapped to a host group on the MD3220i. They are not part of a cluster, they just both have access to the LUNs via the iSCSI intiator and by virtue of the fact they are both part of the "VMWare" host group on the MD3220i. While we have not had any problems, it sounds like we are inviting disaster here.

Again, thank you very much for your advice!

vSPHERE is fully cluster aware.   It actually fits his criteria for proper clustered operation.   :)

JOHNADCO ....

Whew! Thanks for that info .... I can rest a bit easier tonight knowing all is well with THAT side of the house :)