NVMe-oF Subsystems
7 minute read.
You can access the NVMe-of service screen from the:
- dropdown menu on the NVMe-oF Subsystems widget on the Shares screen
- Global Configuration button at the top of the NVMe-oF screen
- NVMe-oF service option on the System > Services screen
The NVMe-oF Global Configuration shows the base NQN for the service.
TrueNAS populates the Base NQN field with the NVMe identifier. Accept this value or click in the field to copy/paste a new, properly formatted Base NQN identifier. NQN is used as the prefix when creating a subsystem, if a subnqn is not supplied. Modifying this value does not change the subnqn of any existing subsystems. We recommend using caution if you change this Base NQN. A particular client might be configured to talk to a particular NQN, so changing this could break the client connection.
Select Generate Cross-port Referrals for Ports on This System if subystems are published through multiple ports and connect-all functionality is desired by clients. If ANA is active, referrals are always generated between the peer ports on each TrueNAS controller node.
Click Save to save changes and close the screen.
Go to the NVMe-oF Global Configuration screen.
Select the Enable Remote Direct Memory Access (RDMA) option. Click Save.
Enabling RDMA allows configuring one or more ports with RDMA selected as the transport when enabled. This option requires an Enterprise license, and you must have an RDMA-capable system and network equipment.
This option is inactive on systems without an Enterprise licenses. If the system is not equipped with required hardware, shows Not enabled, because this system does not support RDMA on the screen.
Go to the NVMe-oF Global Configuration screen. Select the Enable Asymmetric Namespace Access (ANA) option, and click Save.
This allows storage systems to inform hosts about the optimal controller path to access a namespace on Enterprise licensed systems. It is similar to Asymmetric Logical Unit Access (ALUA) in iSCSI.
ANA helps storage arrays communicate to hosts which controller provides the best (lowest latency) path to specific namespaces, enabling intelligent multipathing and improved performance in NVMe-oF environments.
Subsystems correlate to iSCSI targets. Each subsystem has a namespace and port, hosts are optional for added security. The Add Subsystem wizard steps through the subsystem creation process.
You can access the Add Subsystem wizard from the:
- Add button on the NVMe-oF Subsystems widget on the Shares screen
- Add Subsystem button at the top of the NVMe-oF screen
Go to the Add Subsystem wizard, then:
Enter a name for the subsystem. We recommend keeping the name short to avoid any possible issues with accessing the subsystem. A name can consist of upper and lowercase alphabetical characters, numbers, and/or some special characters such as the dash (-), underscore (_), etc.
Leave the NQN set to Generate from global setting. To change it, click on it or the edit icon, and then enter or copy/paste a correctly formatted NQN identification number in the field.
Add a namespace. Click Add to open the Add Namespace screen. The screen opens with the Zvol tab selected. A subsystem can have only one namespace.
To add a new zvol, browse to and select the parent dataset where you want to add the zvol, then click Create Zvol to open the Add Zvol screen. See Creating a Zvol for more information on adding a new zvol.
To use an existing file, click on the Existing File tab, and then browse to select the path to the file.
To add a new file, click on the New File tab, browse to select the parent dataset, then enter a file name, enter the desired file size.
Click Save, then click the breadcrumb at the top of the screen to return to the Add Subsystem wizard.
Click Next to show the Access screen.
Leave Allow any host to connect selected to allow any host to connect, or clear the checkbox to show the Add option for hosts. Adding individual hosts limits access to the subsystem to only the host(s) added.
a. Enter or copy/paste the NQN number obtained from the host system.
b. (Optional) Select Require Host Authentication to show and add authentication setting options.
c. (Optional) Enter the DH-CHAP key obtained from the host system to use when connecting to TrueNAS. Enter or copy/paste the key into the field. To allow TrueNAS to create a key for the host, click in the field to activate Generate Key below the Key for Host to Present field. The field populates with a key. Copy/paste this into the host system connecting to TrueNAS.
d. (Optional) Add a bi-directional key for TrueNAS when it connects to the host system. Click Generate Key below the Key for TrueNAS to Present to populate the field with a key. Copy/paste this into the host system to use when authenticating TrueNAS when it connects to it.
e. (Optional) Select Also use Diffie-Hellman key exchange for additional security.
f. Click Save, then click on the breadcrumb at the top of the screen to return to the Add Subsystem wizard.
Add a port. Click Add to the right of Ports to open the Add Ports screen.
a. Select the transport type. TCP is the default setting. If you have an Enterprise license and your system can support RDMA, this option shows as an available choice.
b. Enter an available port number of at least four digits in length.
c. Select the IP address from the dropdown list.
d. Click Save.
e. Click on the breadcrumb at the top of the screen to close the Add Port screen and return to the Add Subsystem wizard.
Click Save at the bottom of the Add Subsystem wizard screen to add the subsystem.
The Add Zvol screen is accessed from the Add Subsystem wizard after clicking Add to the right of Namespaces. You can also access it from the Namespace widget on the NVMe-oF screen.
Select the subsystem row on the NVMe-oF screen table, then click Add on the Namespaces widget to show the options.
Select Create New to open the Add Namespace screen. Browse to and select the dataset where you want to add the zvol, then click on Create New to open the Add Zvol screen.
To add a new zvol:
Enter a name. We recommend keeping the name short. You can use standard name alpha-numeric, upper or lower case letters, and approved special characters in the name.
Enter the size for the zvol. For example, 10 GiB.
Accept the default settings for the remaining settings, or click the edit icon to show a text entry or dropdown selection field. Enter or select the desired new settings.
(Optional) Set encryption for the zvol.
If the parent dataset where you add the zvol is unencrypted, you can set encryption by clearing the Inherit (unencrypted) checkbox.
If the parent dataset is encrypted you can only change the type of encryption as key or passphrase type. Clear the Inherit (encrypted) checkbox to see the encryption type options.
Click Save, then click the breadcrumb at the top of the screen to return to the previous screen.
