Home > Storage > PowerMax and VMAX > Storage Admin > iSCSI Implementation Guide for Dell EMC Storage Arrays Running PowerMaxOS > Create an iSCSI masking view for the Prod1 host
This section will create an masking view using the IQN from the Prod1 iSCSI host / VM (ENTTME0108). It will demonstrate how to create the host and the host masking view using Unisphere for PowerMax. The masking view will use host IQN as the initiator for the initiator group; it will create and contain a total 200 GB using four volumes in the storage group, and the Prod1 iSCSI targets in the view's port group. An optional step in this section is setting up unidirectional (or One-Way) CHAP authentication for the host initiator and initiator group using Solutions Enabler.
Note: Setting CHAP authentication on an iSCSI initiator is currently not available in Unisphere for PowerMax. It can only be done through Solutions Enabler.
The diagram below is the completed Prod1 environment used by this example. The masking view created in this section will have the following components:
The host used in the example (ENTTME0108) is a Windows Server 2016 host. If the host or virtual machine has not been attached to the network and / or has not previously attempted to log into the PowerMax, then the host administrator will have to provide the initiator IQN to the PowerMax storage administrator. On Windows servers and virtual machines, the host initiator IQN can be found by opening the iSCSI Initiator tool and going to the “Configuration” tab. The host IQN will can be found in the “Initiator Name:” text box.
The host initiator name can also be determined by using the following PowerShell “one liner” command from the Windows host or virtual machine.
PS C:\>(get-initiatorport | where {$_.portaddress -like'*ISCSI*'}).nodeaddress
iqn.1991-05.com.microsoft:enttme0108
After the host IQN has been acquired, create the host in Unisphere by going to PowerMax Array Hosts Hosts and Host Groups and select the “Create” tab.
Once “Create” is selected, the “Create Host” wizard will open. Enter a name for the new host (ENTTME0108-iSCSI); select iSCSI for initiator type; select the “+” button to manually type or copy and paste the host IQN. Press “OK” to add the host IQN to the “Initiators in Host” box. If necessary, host flag options can be selected by clicking “Set Host Flags” in the bottom-left corner of the wizard panel. In the example, the default host flags are used.
If the host had previously logged into the PowerMax, its IQN would already be in the PowerMax internal Login History Database. If this is the case, then the host IQN would show up in the “Available Initiators” box and could be selected without having to enter the host IQN manually.
After adding the initiator to the “Initiators in Host” box, select “Run Now” to create the host.
After creating the iSCSI host, the next step is to create its masking view. This can be easily done by going back to the hosts listings in Unisphere (PowerMax Array Hosts Hosts and Host Groups). Select the newly created host and click on the “Provision Storage to Host” tab.
In an iSCSI masking view in PowerMax, the initiator group uses the host/VM initiator IQN. The Unisphere “Provision Storage to Host” wizard uses the host’s name and IQN and to automatically create the initiator group for the masking view behind the scenes (ENTME0108-iSCSI will be the IG name in the PowerMax and the initiator it contains will be iqn.1991-05.com.microsoft:enttme0108).
The first part of the wizard that requires user input is the creation of the storage group. In the example, the storage group will be named “ENTTME0108_SG” and it will use 4 x 50 GB volumes for a total storage capacity of 200 GB. The example’s storage group will use the “Diamond” service level. This paper will not discuss PowerMax service levels. A link to the PowerMax Service Level White Paper will be provided in the reference section of this document. PowerMax data reduction (both compression and deduplication) is enabled by default. Click “Next” to move on to creating the masking view port group.
The next step in the wizard is to create a new port group used by the masking view. In the example, the port group will be named “Prod1_PG” and will use the Prod1 iSCSI targets. Use the filter icon to bring up the filter bar, and then type “Prod1” to quickly identify the two Prod1 iSCSI targets on the array. Select the two “Prod1” iSCSI targets and the click “Next.”
The final screen of the wizard is the summary screen. The user can at this point set up Host I/O Limits, Enable Compliance Alerts, and run a suitability check. The masking view gets a default name, which is <storage group name>_MV. This name can be changed later by the user. Click “Run Now” to create the masking view.
Monitor the create masking view operation and verify that it completes successfully. After it completes, note the volume numbers that were added to the storage group. If enough volumes of the specific size were already created and available to provide the capacity required, they would be added to the storage group. If there were not enough volumes of the specific size to be added to provide the required capacity, they would be created from free space and then added to the storage group during the creation of the masking view.
This example will set up One-Way CHAP for the “Prod1” host initiator. Setting up CHAP on the initiator is done using the “symaccess set chap” command as follows.
PS C:\> symaccess -sid 0536 -iscsi iqn.1991-05.com.microsoft:enttme0108 set chap –cred iqn.1991-05.com.microsoft:enttme0108 -secret FreeTomBrady
In the above command, the “–iscsi” flag specifies the host initiator IQN. The value used with the “ –cred” flag represents the initiator credential. The initiator and the secret specified by the “-secret” flag must be presented exactly as typed in the above “symaccess” command by the initiator when it attempts to log in to the iSCSI target on the PowerMax array and create an iSCSI session.
The CHAP information for the host initiator is stored in the initiator group properties in the PowerMax ACLX db. This is why an initiator must be in an initiator group or in a masking view prior to enabling CHAP on it. To verify if CHAP is set for a specific initiator, a user does a “symaccess show -details” command on the initiator’s initiator group.
PS C:\ > symaccess -sid 0536 show ENTTME0108-iSCSI -type initiator –detail
Symmetrix ID : 000197900536
Initiator Group Name : ENTTME0108-iSCSI
Last update time : 11:26:14 AM on Tue Dec 31,2019
Group last update time: 11:26:14 AM on Tue Dec 31,2019
Port Flag Overrides : No
Consistent Lun : No
iSCSI Name : iqn.1991-05.com.microsoft:enttme0108
User-generated Name : /
FCID Lockdown : N/A
Heterogeneous Host : No
Port Flag Overrides : No
CHAP Enabled : Yes <---
CHAP Credential : iqn.1991-05.com.microsoft:enttme0108
Type : iSCSI
The above output shows that CHAP has been enabled and what the required credential is for the host initiator.
Note: The secret is never presented in any command output. If the secret is forgotten, CHAP will need to be disabled and the reenabled on the initiator with a new secret. The host will have to use this new secret in order to reestablish the iSCSI session with the PowerMax targets.