This post covers iSCSI Initiator connection management using the Iscsi module for Windows PowerShell available with Windows Server 2012 and Windows 8.
Note: For additional details on management of Windows Disk, Partition, and Volume objects, please refer to the following article:
Managing Storage with Windows PowerShell on Windows Server 2012 http://blogs.msdn.com/b/san/archive/2012/07/03/managing-storage-with-windows-powershell-on-windows-server-2012.aspx
Prior to Windows Server 2012, iSCSI Initiator connection management via the command line was performed using the iSCSICLI.exe tool from a CMD prompt. The legacy tool iSCSICLI.exe is superseded by the iSCSI module for Windows PowerShell available on Windows Server 2012 and Windows 8 (only).
The iSCSI module requires that the iSCSI Service and its associated firewall rule be enabled in order to report information back. This can be accomplished via either of the following methods:
Note: at a minimum, the Windows Firewall rule for the iSCSI Initiator Service must also be enabled for outgoing traffic.
PS C:\WINDOWS\system32> Get-NetFirewallServiceFilter -Service msiscsi | Get-NetFirewallRule | Select DisplayGroup,DisplayName,Enabled
Connecting to a new iSCSI Target is a two-step process. First an iSCSI Target Portal is established using the New-iSCSITargetPortal cmdlet, and then a connection is established using the Connect-iSCSITarget cmdlet.
For example, I have a new iSCSI target named DeepSpace that I need to establish a connection with. I would complete the connection using the following command:
New-IscsiTargetPortal –TargetPortalAddress DeepSpace
After a new target portal is created, the iSCSI target, and its connection status are displayed via the Get-IscsiTarget cmdlet as shown below:
To connect to all available iSCSI Targets, use the following command:
Get-IscsiTarget | Connect-IscsiTarget
View currently connected iSCSI Sessions and connections using the following commands;
Get-iSCSISession | Get-Disk
You can list the current iSCSI Qualified Name (IQN) by using the following command: The iSCSI IQN for the initiator is typically used when configuring masking sets with an iSCSI Target device to allow access by a specific initiator to an iSCSI Target device.
An iSCSI Session that has a property of IsPersistent = $True will automatically attempt reconnection on a system reboot. For example, the connection below is not persistent:
PS C:\WINDOWS\system32> Get-IscsiSession
AuthenticationType : NONE InitiatorInstanceName : ROOT\ISCSIPRT\0000_0 InitiatorNodeAddress : iqn.1991-05.com.microsoft:deepcore.contoso.com InitiatorPortalAddress : 0.0.0.0 InitiatorSideIdentifier : 400001370000 IsConnected : True IsDataDigest : False IsDiscovered : False IsHeaderDigest : False IsPersistent : False NumberOfConnections : 1 SessionIdentifier : fffffa80144f8430-4000013700000003 TargetNodeAddress : iqn.1991-05.com.microsoft:deepspace-deepcore-target TargetSideIdentifier : 0300 PSComputerName :
When connecting to a new iSCSI Target using the Connect-iSCSITarget cmdlet, persistence is managed via the –IsPersistent Boolean value.
Get-iSCSITarget | Connect-IscsiTarget –IsPersistent $False would prevent the new connection from persisting across reboots.
Note: Connections are persistent by default unless overridden by specifying –IsPersistent $False
For an existing session, if the session is not persistent, it can be made persistent by piping the session to the Register-iSCSISession cmdlet. For example:
PS C:\WINDOWS\system32> Get-IscsiSession | Where-Object IsPersistent -eq $False
In this case, since I have an iSCSI Session which is not persistent, I could pipe this object to Register-IscsiSession to make it persistent.
Get-IscsiSession | Register-IscsiSession
To connect to an iSCSI Target which requires the use of a CHAP secret, you can use the following cmdlet options, and select the appropriate type of CHAP secret to use in the –AuthenticationType parameter.
Get-iScsiTarget | Connect-iScsitarget –AuthenticationType ONEWAYCHAP –ChapUserName <username> -ChapSecret <secret>
Connecting multiple network adapters in conjunction with iSCSI and MPIO:
Note: MPIO is available on Windows Server versions only.
Get-NetIPAddress –AddressFamily IPv4 –PrefixOrigin DHCP
For example, if I stored the output of the above command in the variable $Nics on a machine with 2 network adapters, then $Nics.IpAddress returns the IP address for my first NIC, and $Nics.Ipaddress returns the IP address for my second NIC.
For the rest of this example, I have used the above to populate two variables;
$Nic1 = $Nics
$Nic2 = $Nics
Tip: By configuring MPIO to automatically claim iSCSI devices (for example) before any are connected, you may be able to avoid an extra reboot when the disks are claimed.
In the example below, I am installing the MPIO feature, enabling automatic claiming of all iSCSI disks, and setting the default load balance policy in MPIO to Round Robin:
# Enable the MPIO Feature Enable-WindowsOptionalFeature -Online -FeatureName MultipathIO # Enable automatic claiming of iSCSI devices for MPIO Enable-MSDSMAutomaticClaim -BusType iSCSI # Set the default load balance policy of all newly claimed devices to Round Robin Set-MSDSMGlobalDefaultLoadBalancePolicy -Policy RR
First we will need to define the targetportal to point to the iSCSI Target. In my example below, the target portal is named DeepSpace
Lastly, we would create one MPIO-enabled iSCSI connection per network adapter using the following commands:
Get-IscsiTarget | Connect-IscsiTarget -IsPersistent $True –IsMultipathEnabled $True –InitiatorPortalAddress $Nic1.IPAddress
Get-IscsiTarget | Connect-IscsiTarget -IsPersistent $True –IsMultipathEnabled $True –InitiatorPortalAddress $Nic2.IPAddress
Get-iSCSIConnection displays the IP address for the network adapter used with this connection(s). For example;
The following example shows listing all disks associated with the active iSCSI Connection(s) in the system.
This process can also be reversed to determine the iSCSI connections for a specific Disk object such as by passing the output of Get-Disk 1 to Get-iSCSIConnection.
For a complete listing of the cmdlets contained in the iSCSI module for Windows PowerShell, please refer to the following document on TechNet: http://technet.microsoft.com/library/hh826099.aspx
iSCSI Initiator WMI V2 Classes for Windows Server 2012 and Windows 8 http://msdn.microsoft.com/en-us/library/windows/desktop/hh968118(v=vs.85).aspx