Configure RHEL 9.6 for NVMe-oF with ONTAP storage

10/08/2025 Contributors

Red Hat Enterpirse Linux (RHEL) hosts support the NVMe over Fibre Channel (NVMe/FC) and NVMe over TCP (NVMe/TCP) protocols with Asymmetric Namespace Access (ANA). ANA provides multipathing functionality equivalent to asymmetric logical unit access (ALUA) in iSCSI and FCP environments.

Learn how to configure NVMe over Fabrics (NVMe-oF) hosts for Red Hat Enterprise Linux (RHEL) 9.6. For more support and feature information, see NVME-oF Overview.

NVMe-oF with RHEL 9.6 has the following known limitations:

Avoid issuing the nvme disconnect-all command on systems booting from SAN over NVMe-TCP or NVMe-FC namespaces because it disconnects both root and data filesystems and might lead to system instability.

Step 1: Optionally, enable SAN booting

You can configure your host to use SAN booting to simplify deployment and improve scalability. Use the Interoperability Matrix Tool to verify that your Linux OS, host bus adapter (HBA), HBA firmware, HBA boot BIOS, and ONTAP version support SAN booting.

Steps

Create a NVMe namespace and map it to the host.
Enable SAN booting in the server BIOS for the ports to which the SAN boot namespace is mapped.

For information on how to enable the HBA BIOS, see your vendor-specific documentation.
Reboot the host and verify that the OS is up and running.

Step 2: Verify the software version and NVMe configuration

Check that your system meets software requirements and verify NVMe package installations and host configuration.

Steps

Install RHEL 9.6 on the server. After the installation is complete, verify that you are running the required RHEL 9.6 kernel:
```
uname -r
```
Example RHEL kernel version:
```
5.14.0-570.12.1.el9_6.x86_64
```
Install the nvme-cli package:
```
rpm -qa|grep nvme-cli
```
The following example shows an nvme-cli package version:
```
nvme-cli-2.11-5.el9.x86_64
```
Install the libnvme package:
```
rpm -qa|grep libnvme
```
The following example shows an libnvme package version:
```
libnvme-1.11.1-1.el9.x86_64
```
On the host, check the hostnqn string at /etc/nvme/hostnqn:
```
cat /etc/nvme/hostnqn
```
The following example shows an hostnqn version:
```
nqn.2014-08.org.nvmexpress:uuid:4c4c4544-0056-5410-8048-b9c04f425633
```

Verify that the hostnqn string matches the hostnqn string for the corresponding subsystem on the ONTAP array:

::> vserver nvme subsystem host show -vserver vs_nvme_194_rhel96

Show example

Vserver Subsystem Priority  Host NQN
------- --------- --------  ------------------------------------------------
vs_ nvme_194_rhel96
        nvme4
                  regular   nqn.2014-08.org.nvmexpress:uuid:4c4c4544-0056-5410-8048- c7c04f425633
        nvme_1
                  regular   nqn.2014-08.org.nvmexpress:uuid:4c4c4544-0056-5410-8048- c7c04f425633
        nvme_2
                  regular   nqn.2014-08.org.nvmexpress:uuid:4c4c4544-0056-5410-8048- c7c04f425633
        nvme_3
                  regular   nqn.2014-08.org.nvmexpress:uuid:4c4c4544-0056-5410-8048- c7c04f425633
4 entries were displayed.

If the hostnqn strings do not match, use the vserver modify command to update the hostnqn string on your corresponding ONTAP storage system subsystem to match the hostnqn string from /etc/nvme/hostnqn on the host.

Step 3: Configure NVMe/FC and NVMe/TCP

Configure NVMe/FC with Broadcom/Emulex or Marvell/QLogic adapters, or configure NVMe/TCP using manual discovery and connect operations.

FC - Broadcom/Emulex

Configure NVMe/FC for a Broadcom/Emulex adapter.

Steps

Verify that you are using the supported adapter model:

Display the model names:

cat /sys/class/scsi_host/host*/modelname

You should see the following output:

LPe36002-M64
LPe36002-M64

Display the model descriptions:

cat /sys/class/scsi_host/host*/modeldesc

You should see output similar to the following example:

Emulex LightPulse LPe36002-M64 2-Port 64Gb Fibre Channel Adapter
Emulex LightPulse LPe36002-M64 2-Port 64Gb Fibre Channel Adapter

Verify that you are using the recommended Broadcom lpfc firmware and inbox driver:
1. Display the firmware version:
  cat /sys/class/scsi_host/host*/fwrev
  The command returns the firmware versions:
  14.0.539.16, sli-4:6:d 14.0.539.16, sli-4:6:d
2. Display the inbox driver version:
  cat /sys/module/lpfc/version
  The following example shows a driver version:
  0:14.4.0.6
For the current list of supported adapter driver and firmware versions, see the Interoperability Matrix Tool.

Verify that lpfc_enable_fc4_type is set to 3:

cat /sys/module/lpfc/parameters/lpfc_enable_fc4_type

Verify that you can view your initiator ports:
```
cat /sys/class/fc_host/host*/port_name
```
The following example shows port identities:
```
0x2100f4c7aa0cd7c2
0x2100f4c7aa0cd7c3
```
Verify that your initiator ports are online:
```
cat /sys/class/fc_host/host*/port_state
```
You should see the following output:
```
Online
Online
```

Verify that the NVMe/FC initiator ports are enabled and that the target ports are visible:

cat /sys/class/scsi_host/host*/nvme_info

Show example

NVME Initiator Enabled
XRI Dist lpfc0 Total 6144 IO 5894 ELS 250
NVME LPORT lpfc0 WWPN x100000109b954518 WWNN x200000109b954518 DID x000000 ONLINE

NVME Statistics
LS: Xmt 0000000000 Cmpl 0000000000 Abort 00000000
LS XMIT: Err 00000000  CMPL: xb 00000000 Err 00000000
Total FCP Cmpl 0000000000000000 Issue 0000000000000000 OutIO 0000000000000000
          abort 00000000 noxri 00000000 nondlp 00000000 qdepth 00000000 wqerr 00000000 err 00000000
FCP CMPL: xb 00000000 Err 00000000

NVME Initiator Enabled
XRI Dist lpfc1 Total 6144 IO 5894 ELS 250
NVME LPORT lpfc1 WWPN x100000109b954519 WWNN x200000109b954519 DID x020500 ONLINE

NVME Statistics
LS: Xmt 0000000000 Cmpl 0000000000 Abort 00000000
LS XMIT: Err 00000000  CMPL: xb 00000000 Err 00000000
Total FCP Cmpl 0000000000000000 Issue 0000000000000000 OutIO 0000000000000000
         abort 00000000 noxri 00000000 nondlp 00000000 qdepth 00000000 wqerr 00000000 err 00000000
FCP CMPL: xb 00000000 Err 00000000

NVME Initiator Enabled
XRI Dist lpfc2 Total 6144 IO 5894 ELS 250
NVME LPORT lpfc2 WWPN x100000109bf044b1 WWNN x200000109bf044b1 DID x022a00 ONLINE
NVME RPORT       WWPN x200bd039eaa7dfc8 WWNN x2008d039eaa7dfc8 DID x021319 TARGET DISCSRVC ONLINE
NVME RPORT       WWPN x2155d039eaa7dfc8 WWNN x2154d039eaa7dfc8 DID x02130f TARGET DISCSRVC ONLINE
NVME RPORT       WWPN x2001d039eaa7dfc8 WWNN x2000d039eaa7dfc8 DID x021310 TARGET DISCSRVC ONLINE
NVME RPORT       WWPN x200dd039eaa7dfc8 WWNN x2008d039eaa7dfc8 DID x020b15 TARGET DISCSRVC ONLINE
NVME RPORT       WWPN x2156d039eaa7dfc8 WWNN x2154d039eaa7dfc8 DID x020b0d TARGET DISCSRVC ONLINE
NVME RPORT       WWPN x2003d039eaa7dfc8 WWNN x2000d039eaa7dfc8 DID x020b10 TARGET DISCSRVC ONLINE

NVME Statistics
LS: Xmt 0000003049 Cmpl 0000003049 Abort 00000000
LS XMIT: Err 00000000  CMPL: xb 00000000 Err 00000000
Total FCP Cmpl 0000000018f9450b Issue 0000000018f5de57 OutIO fffffffffffc994c
          abort 000036d3 noxri 00000313 nondlp 00000c8d qdepth 00000000 wqerr 00000064 err 00000000
FCP CMPL: xb 000036d1 Err 000fef0f

NVME Initiator Enabled
XRI Dist lpfc3 Total 6144 IO 5894 ELS 250
NVME LPORT lpfc3 WWPN x100000109bf044b2 WWNN x200000109bf044b2 DID x021b00 ONLINE
NVME RPORT       WWPN x2062d039eaa7dfc8 WWNN x2008d039eaa7dfc8 DID x022915 TARGET DISCSRVC ONLINE
NVME RPORT       WWPN x2157d039eaa7dfc8 WWNN x2154d039eaa7dfc8 DID x02290f TARGET DISCSRVC ONLINE
NVME RPORT       WWPN x2002d039eaa7dfc8 WWNN x2000d039eaa7dfc8 DID x022910 TARGET DISCSRVC ONLINE
NVME RPORT       WWPN x2065d039eaa7dfc8 WWNN x2008d039eaa7dfc8 DID x020119 TARGET DISCSRVC ONLINE
NVME RPORT       WWPN x2158d039eaa7dfc8 WWNN x2154d039eaa7dfc8 DID x02010d TARGET DISCSRVC ONLINE
NVME RPORT       WWPN x2004d039eaa7dfc8 WWNN x2000d039eaa7dfc8 DID x020110 TARGET DISCSRVC ONLINE

NVME Statistics
LS: Xmt 0000002f2c Cmpl 0000002f2c Abort 00000000
LS XMIT: Err 00000000  CMPL: xb 00000000 Err 00000000
Total FCP Cmpl 000000001aaf3eb5 Issue 000000001aab4373 OutIO fffffffffffc04be
          abort 000035cc noxri 0000038c nondlp 000009e3 qdepth 00000000 wqerr 00000082 err 00000000
FCP CMPL: xb 000035cc Err 000fcfc0

FC - Marvell/QLogic

Configure NVMe/FC for a Marvell/QLogic adapter.

Steps

Verify that you are using the supported adapter driver and firmware versions:
```
cat /sys/class/fc_host/host*/symbolic_name
```
The following example shows driver and firmware versions:
```
QLE2872 FW:v9.15.00 DVR:v10.02.09.300-k
QLE2872 FW:v9.15.00 DVR:v10.02.09.300-k
```
Verify that ql2xnvmeenable is set. This enables the Marvell adapter to function as an NVMe/FC initiator:
```
cat /sys/module/qla2xxx/parameters/ql2xnvmeenable
```
The expected output is 1.

TCP

The NVMe/TCP protocol doesn't support the auto-connect operation. Instead, you can discover the NVMe/TCP subsystems and namespaces by performing the NVMe/TCP connect or connect-all operations manually.

Steps

Check that the initiator port can get the discovery log page data across the supported NVMe/TCP LIFs:

nvme discover -t tcp -w host-traddr -a traddr

Show example

nvme discover -t tcp -w 192.168.20.1 -a 192.168.20.20

Discovery Log Number of Records 8, Generation counter 18
=====Discovery Log Entry 0======
trtype:  tcp
adrfam:  ipv4
subtype: current discovery subsystem
treq:    not specified
portid:  4
trsvcid: 8009
subnqn:  nqn.1992-08.com.netapp:sn.64e65e6caae711ef9668d039ea951c46:discovery
traddr:  192.168.21.21
eflags:  explicit discovery connections, duplicate discovery information
sectype: none
=====Discovery Log Entry 1======
trtype:  tcp
adrfam:  ipv4
subtype: current discovery subsystem
treq:    not specified
portid:  2
trsvcid: 8009
subnqn:  nqn.1992-08.com.netapp:sn.64e65e6caae711ef9668d039ea951c46:discovery
traddr:  192.168.20.21
eflags:  explicit discovery connections, duplicate discovery information
sectype: none
=====Discovery Log Entry 2======
trtype:  tcp
adrfam:  ipv4
subtype: current discovery subsystem
treq:    not specified
portid:  3
trsvcid: 8009
subnqn:  nqn.1992-08.com.netapp:sn.64e65e6caae711ef9668d039ea951c46:discovery
traddr:  192.168.21.20
eflags:  explicit discovery connections, duplicate discovery information
sectype: none
=====Discovery Log Entry 3======
trtype:  tcp
adrfam:  ipv4
subtype: current discovery subsystem
treq:    not specified
portid:  1
trsvcid: 8009
subnqn:  nqn.1992-08.com.netapp:sn.64e65e6caae711ef9668d039ea951c46:discovery
traddr:  192.168.20.20
eflags:  explicit discovery connections, duplicate discovery information
sectype: none
=====Discovery Log Entry 4======
trtype:  tcp
adrfam:  ipv4
subtype: nvme subsystem
treq:    not specified
portid:  4
trsvcid: 4420
subnqn:  nqn.1992-08.com.netapp:sn.64e65e6caae711ef9668d039ea951c46:subsystem.rhel96_tcp_subsystem
traddr:  192.168.21.21
eflags:  none
sectype: none
=====Discovery Log Entry 5======
trtype:  tcp
adrfam:  ipv4
subtype: nvme subsystem
treq:    not specified
portid:  2
trsvcid: 4420
subnqn:  nqn.1992-08.com.netapp:sn.64e65e6caae711ef9668d039ea951c46:subsystem.rhel96_tcp_subsystem
traddr:  192.168.20.21
eflags:  none
sectype: none
=====Discovery Log Entry 6======
trtype:  tcp
adrfam:  ipv4
subtype: nvme subsystem
treq:    not specified
portid:  3
trsvcid: 4420
subnqn:  nqn.1992-08.com.netapp:sn.64e65e6caae711ef9668d039ea951c46:subsystem.rhel96_tcp_subsystem
traddr:  192.168.21.20
eflags:  none
sectype: none
=====Discovery Log Entry 7======
trtype:  tcp
adrfam:  ipv4
subtype: nvme subsystem
treq:    not specified
portid:  1
trsvcid: 4420
subnqn:  nqn.1992-08.com.netapp:sn.64e65e6caae711ef9668d039ea951c46:subsystem.rhel96_tcp_subsystem
traddr:  192.168.20.20
eflags:  none
sectype: none

Verify that the other NVMe/TCP initiator-target LIF combinations can successfully retrieve discovery log page data:

nvme discover -t tcp -w host-traddr -a traddr

Show example

nvme discover -t tcp -w 192.168.20.1 -a 192.168.20.20
nvme discover -t tcp -w 192.168.21.1 -a 192.168.21.20
nvme discover -t tcp -w 192.168.20.1 -a 192.168.20.21
nvme discover -t tcp -w 192.168.21.1 -a 192.168.21.21

Run the nvme connect-all command across all the supported NVMe/TCP initiator-target LIFs across the nodes:

nvme connect-all -t tcp -w host-traddr -a traddr

Show example

nvme	connect-all	-t	tcp	-w	192.168.20.1	-a	192.168.20.20
nvme	connect-all	-t	tcp	-w	192.168.21.1	-a	192.168.21.20
nvme	connect-all	-t	tcp	-w	192.168.20.1	-a	192.168.20.21
nvme	connect-all	-t	tcp	-w	192.168.21.1	-a	192.168.21.21

Beginning with RHEL 9.4, the setting for the NVMe/TCP ctrl_loss_tmo timeout is automatically set to "off". As a result:

There are no limits on the number of retries (indefinite retry).
You don't need to manually configure a specific ctrl_loss_tmo timeout duration when using the nvme connect or nvme connect-all commands (option -l ).
The NVMe/TCP controllers don't experience timeouts in the event of a path failure and remain connected indefinitely.

Modify the iopolicy in the udev rules

RHEL 9.6 sets the default iopolicy for NVMe-oF to round-robin. If you want to change the iopolicy to queue-depth, modify the udev rules file as follows:

Open the udev rules file in a text editor with root privileges:
```
/usr/lib/udev/rules.d/71-nvmf-netapp.rules
```
You should see the following output:
```
vi /usr/lib/udev/rules.d/71-nvmf-netapp.rules
```

Find the line that sets iopolicy for the NetApp ONTAP Controller.

The following example shows an example rule:

ACTION=="add", SUBSYSTEM=="nvme-subsystem", ATTR{subsystype}=="nvm", ATTR{model}=="NetApp ONTAP Controller", ATTR{iopolicy}="round-robin"

Modify the rule so that round-robin becomes queue-depth:

ACTION=="add", SUBSYSTEM=="nvme-subsystem", ATTR{subsystype}=="nvm", ATTR{model}=="NetApp ONTAP Controller", ATTR{iopolicy}="queue-depth"

Run the following commands to reload the udev rules and apply the changes:
```
udevadm control --reload
udevadm trigger --subsystem-match=nvme-subsystem
```
Verify the current iopolicy for your subsystem. Replace <subsystem> with the appropriate name, for example, nvme-subsys0.
```
cat /sys/class/nvme-subsystem/<subsystem>/iopolicy
```
You should see the following output:
```
queue-depth.
```

The new iopolicy applies automatically to matching NetApp ONTAP Controller devices. No reboot is required.

Step 4: Optionally, enable 1MB I/O for NVMe/FC

ONTAP reports a Max Data Transfer Size (MDTS) of 8 in the Identify Controller data. This means the maximum I/O request size can be up to 1MB. To issue I/O requests of size 1MB for a Broadcom NVMe/FC host, you should increase the lpfc value of the lpfc_sg_seg_cnt parameter to 256 from the default value of 64.

These steps don't apply to Qlogic NVMe/FC hosts.

Steps

Set the lpfc_sg_seg_cnt parameter to 256:
```
cat /etc/modprobe.d/lpfc.conf
```
You should see an output similar to the following example:
```
options lpfc lpfc_sg_seg_cnt=256
```
Run the dracut -f command, and reboot the host.

Verify that the value for lpfc_sg_seg_cnt is 256:

cat /sys/module/lpfc/parameters/lpfc_sg_seg_cnt

Step 5: Verify NVMe boot services

The nvmefc-boot-connections.service and nvmf-autoconnect.service boot services included in the NVMe/FC nvme-cli package are automatically enabled when the system boots.

After booting completes, verify that the nvmefc-boot-connections.service and nvmf-autoconnect.service boot services are enabled.

Steps

Verify that nvmf-autoconnect.service is enabled:

systemctl status nvmf-autoconnect.service

Show example output

nvmf-autoconnect.service - Connect NVMe-oF subsystems automatically during boot
     Loaded: loaded (/usr/lib/systemd/system/nvmf-autoconnect.service; enabled; preset: disabled)
     Active: inactive (dead)

Jun 10 04:06:26 SR630-13-201.lab.eng.btc.netapp.in systemd[1]: Starting Connect NVMe-oF subsystems automatically during boot...
Jun 10 04:06:26 SR630-13-201.lab.eng.btc.netapp.in systemd[1]: nvmf-autoconnect.service: Deactivated successfully.
Jun 10 04:06:26 SR630-13-201.lab.eng.btc.netapp.in systemd[1]: Finished Connect NVMe-oF subsystems automatically during boot.

Verify that nvmefc-boot-connections.service is enabled:

systemctl status nvmefc-boot-connections.service

Show example output

nvmefc-boot-connections.service - Auto-connect to subsystems on FC-NVME devices found during boot
     Loaded: loaded (/usr/lib/systemd/system/nvmefc-boot-connections.service; enabled; preset: enabled)
     Active: inactive (dead) since Tue 2025-06-10 01:08:36 EDT; 2h 59min ago
   Main PID: 7090 (code=exited, status=0/SUCCESS)
        CPU: 30ms

Jun 10 01:08:36 localhost systemd[1]: Starting Auto-connect to subsystems on FC-NVME devices found during boot...
Jun 10 01:08:36 localhost systemd[1]: nvmefc-boot-connections.service: Deactivated successfully.
Jun 10 01:08:36 localhost systemd[1]: Finished Auto-connect to subsystems on FC-NVME devices found during boot.

Step 6: Verify the multipathing configuration

Verify that the in-kernel NVMe multipath status, ANA status, and ONTAP namespaces are correct for the NVMe-oF configuration.

Steps

Verify that the in-kernel NVMe multipath is enabled:
```
cat /sys/module/nvme_core/parameters/multipath
```
You should see the following output:
```
Y
```
Verify that the appropriate NVMe-oF settings (such as, model set to NetApp ONTAP Controller and load balancing iopolicy set to round-robin) for the respective ONTAP namespaces correctly reflect on the host:
1. Display the subsystems:
  cat /sys/class/nvme-subsystem/nvme-subsys*/model
  You should see the following output:
  NetApp ONTAP Controller NetApp ONTAP Controller
2. Display the policy:
  cat /sys/class/nvme-subsystem/nvme-subsys*/iopolicy
  You should see the following output:
  queue-depth queue-depth

Verify that the namespaces are created and correctly discovered on the host:

nvme list

Show example

Node         SN                   Model
---------------------------------------------------------
/dev/nvme4n1 81Ix2BVuekWcAAAAAAAB	NetApp ONTAP Controller


Namespace Usage    Format             FW             Rev
-----------------------------------------------------------
1                 21.47 GB / 21.47 GB	4 KiB + 0 B   FFFFFFFF

Verify that the controller state of each path is live and has the correct ANA status:

NVMe/FC

nvme list-subsys /dev/nvme4n5

Show example

nvme-subsys4 - NQN=nqn.1992-08.com.netapp:sn.3a5d31f5502c11ef9f50d039eab6cb6d:subsystem.nvme_1
               hostnqn=nqn.2014-08.org.nvmexpress:uuid:e6dade64-216d-
11ec-b7bb-7ed30a5482c3
iopolicy=round-robin\
+- nvme1 fc traddr=nn-0x2082d039eaa7dfc8:pn-0x2088d039eaa7dfc8,host_traddr=nn-0x20000024ff752e6d:pn-0x21000024ff752e6d live optimized
+- nvme12 fc traddr=nn-0x2082d039eaa7dfc8:pn-0x208ad039eaa7dfc8,host_traddr=nn-0x20000024ff752e6d:pn-0x21000024ff752e6d live non-optimized
+- nvme10 fc traddr=nn-0x2082d039eaa7dfc8:pn-0x2087d039eaa7dfc8,host_traddr=nn-0x20000024ff752e6c:pn-0x21000024ff752e6c live non-optimized
+- nvme3 fc traddr=nn-0x2082d039eaa7dfc8:pn-0x2083d039eaa7dfc8,host_traddr=nn-0x20000024ff752e6c:pn-0x21000024ff752e6c live optimized

NVMe/TCP

nvme list-subsys /dev/nvme1n1

Show example

nvme-subsys5 - NQN=nqn.1992-08.com.netapp:sn.0f4ba1e74eb611ef9f50d039eab6cb6d:subsystem.nvme_tcp_3
hostnqn=nqn.2014-08.org.nvmexpress:uuid:4c4c4544-0035-5910-804b-b5c04f444d33
iopolicy=round-robin
\
+- nvme13 tcp traddr=192.168.2.25,trsvcid=4420,host_traddr=192.168.2.31,
src_addr=192.168.2.31 live optimized
+- nvme14 tcp traddr=192.168.2.24,trsvcid=4420,host_traddr=192.168.2.31,
src_addr=192.168.2.31 live non-optimized
+- nvme5 tcp traddr=192.168.1.25,trsvcid=4420,host_traddr=192.168.1.31,
src_addr=192.168.1.31 live optimized
+- nvme6 tcp traddr=192.168.1.24,trsvcid=4420,host_traddr=192.168.1.31,
src_addr=192.168.1.31 live non-optimized

Verify that the NetApp plug-in displays the correct values for each ONTAP namespace device:

Column

nvme netapp ontapdevices -o column

Show example

Device        Vserver   Namespace Path
----------------------- ------------------------------
/dev/nvme1n1     linux_tcnvme_iscsi        /vol/tcpnvme_1_0_0/tcpnvme_ns

NSID       UUID                                   Size
------------------------------------------------------------
1    5f7f630d-8ea5-407f-a490-484b95b15dd6   21.47GB

JSON

nvme netapp ontapdevices -o json

Show example

{
  "ONTAPdevices":[
    {
      "Device":"/dev/nvme1n1",
      "Vserver":"linux_tcnvme_iscsi",
      "Namespace_Path":"/vol/tcpnvme_1_0_0/tcpnvme_ns",
      "NSID":1,
      "UUID":"5f7f630d-8ea5-407f-a490-484b95b15dd6",
      "Size":"21.47GB",
      "LBA_Data_Size":4096,
      "Namespace_Size":5242880
    },
]
}

Step 7: Set up secure in-band authentication

Beginning with ONTAP 9.12.1, secure in-band authentication is supported over NVMe/TCP between a RHEL 10.0 host and an ONTAP controller.

Each host or controller must be associated with a DH-HMAC-CHAP key to set up secure authentication. A DH-HMAC-CHAP key is a combination of the NQN of the NVMe host or controller and an authentication secret configured by the administrator. To authenticate its peer, an NVMe host or controller must recognize the key associated with the peer.

Set up secure in-band authentication using the CLI or a config JSON file. If you need to specify different dhchap keys for different subsystems, you must use a config JSON file.

CLI

Set up secure in-band authentication using the CLI.

Steps

Obtain the host NQN:
```
cat /etc/nvme/hostnqn
```

Generate the dhchap key for the RHEL 9.6 host.

The following output describes the gen-dhchap-key command parameters:

nvme gen-dhchap-key -s optional_secret -l key_length {32|48|64} -m HMAC_function {0|1|2|3} -n host_nqn
•	-s secret key in hexadecimal characters to be used to initialize the host key
•	-l length of the resulting key in bytes
•	-m HMAC function to use for key transformation
0 = none, 1- SHA-256, 2 = SHA-384, 3=SHA-512
•	-n host NQN to use for key transformation

In the following example, a random dhchap key with HMAC set to 3 (SHA-512) is generated.

nvme gen-dhchap-key -m 3 -n nqn.2014-
08.org.nvmexpress:uuid:e6dade64-216d-11ec-b7bb-7ed30a5482c3
DHHC-1:03:wSpuuKbBHTzC0W9JZxMBsYd9JFV8Si9aDh22k2BR/4m852vH7KGlrJeMpzhmyjDWOo0PJJM6yZsTeEpGkDHMHQ255+g=:

On the ONTAP controller, add the host and specify both dhchap keys:

vserver nvme subsystem host add -vserver <svm_name> -subsystem <subsystem> -host-nqn <host_nqn> -dhchap-host-secret <authentication_host_secret> -dhchap-controller-secret <authentication_controller_secret> -dhchap-hash-function {sha-256|sha-512} -dhchap-group {none|2048-bit|3072-bit|4096-bit|6144-bit|8192-bit}

A host supports two types of authentication methods, unidirectional and bidirectional. On the host, connect to the ONTAP controller and specify dhchap keys based on the chosen authentication method:
```
nvme connect -t tcp -w <host-traddr> -a <tr-addr> -n <host_nqn> -S <authentication_host_secret> -C <authentication_controller_secret>
```

Validate the nvme connect authentication command by verifying the host and controller dhchap keys:

Verify the host dhchap keys:

cat /sys/class/nvme-subsystem/<nvme-subsysX>/nvme*/dhchap_secret

Show example output for a unidirectional configuration

cat /sys/class/nvme-subsystem/nvme-subsys1/nvme*/dhchap_secret
DHHC-1:01:CNxTYq73T9vJk0JpOfDBZrhDCqpWBN4XVZI5WxwPgDUieHAi:
DHHC-1:01:CNxTYq73T9vJk0JpOfDBZrhDCqpWBN4XVZI5WxwPgDUieHAi:
DHHC-1:01:CNxTYq73T9vJk0JpOfDBZrhDCqpWBN4XVZI5WxwPgDUieHAi:
DHHC-1:01:CNxTYq73T9vJk0JpOfDBZrhDCqpWBN4XVZI5WxwPgDUieHAi:

Verify the controller dhchap keys:

cat /sys/class/nvme-subsystem/<nvme-subsysX>/nvme*/dhchap_ctrl_secret

Show example output for a bidirectional configuration

cat /sys/class/nvme-subsystem/nvme-
subsys6/nvme*/dhchap_ctrl_secret
DHHC-1:03:wSpuuKbBHTzC0W9JZxMBsYd9JFV8Si9aDh22k2BR/4m852vH7KGlrJeMpzhmyjDWOo0PJJM6yZsTeEpGkDHMHQ255+g=:
DHHC-1:03:wSpuuKbBHTzC0W9JZxMBsYd9JFV8Si9aDh22k2BR/4m852vH7KGlrJeMpzhmyjDWOo0PJJM6yZsTeEpGkDHMHQ255+g=:
DHHC-1:03:wSpuuKbBHTzC0W9JZxMBsYd9JFV8Si9aDh22k2BR/4m852vH7KGlrJeMpzhmyjDWOo0PJJM6yZsTeEpGkDHMHQ255+g=:
DHHC-1:03:wSpuuKbBHTzC0W9JZxMBsYd9JFV8Si9aDh22k2BR/4m852vH7KGlrJeMpzhmyjDWOo0PJJM6yZsTeEpGkDHMHQ255+g=:

JSON

When multiple NVMe subsystems are available on the ONTAP controller, you can use the /etc/nvme/config.json file with the nvme connect-all command.

Use the -o option to generate the JSON file. Refer to the NVMe connect-all man pages for more syntax options.

Steps

Configure the JSON file.

In the following example, dhchap_key corresponds to dhchap_secret and dhchap_ctrl_key corresponds to dhchap_ctrl_secret.

Show example

cat /etc/nvme/config.json
[
{
  "hostnqn":"nqn.2014-08.org.nvmexpress:uuid:9796c1ec-0d34-11eb-
  b6b2-3a68dd3bab57",
  "hostid":"b033cd4fd6db4724adb48655bfb55448",
  "dhchap_key":" DHHC-1:01:CNxTYq73T9vJk0JpOfDBZrhDCqpWBN4XVZI5WxwPgDUieHAi:"
},
{
  "hostnqn":"nqn.2014-08.org.nvmexpress:uuid:4c4c4544-0035-5910-
  804b-b5c04f444d33",
  "subsystems":[
        {
          "nqn":"nqn.1992-
          08.com.netapp:sn.0f4ba1e74eb611ef9f50d039eab6cb6d:subsystem.bidi
          r_DHCP",
          "ports":[
              {
                  "transport":"tcp",
                    "traddr":" 192.168.1.24 ",
                  "host_traddr":" 192.168.1.31 ",
                  "trsvcid":"4420",
                  "dhchap_ctrl_key":"DHHC-
                  1:03: wSpuuKbBHTzC0W9JZxMBsYd9JFV8Si9aDh22k2BR/4m852vH7KGlrJeMpzhmyjDWOo0PJJM6yZsTeEpGkDHMHQ255+g=:"
              },
              {
                  "transport":"tcp",
                  "traddr":" 192.168.1.25 ",
                  "host_traddr":" 192.168.1.31",
                  "trsvcid":"4420",
                  "dhchap_ctrl_key":"DHHC-
                  1:03: wSpuuKbBHTzC0W9JZxMBsYd9JFV8Si9aDh22k2BR/4m852vH7KGlrJeMpzhmyjDWOo0PJJM6yZsTeEpGkDHMHQ255+g=:"
              },
              {
                  "transport":"tcp",
                 "traddr":" 192.168.2.24 ",
                  "host_traddr":" 192.168.2.31",
                  "trsvcid":"4420",
                  "dhchap_ctrl_key":"DHHC-
                  1:03: wSpuuKbBHTzC0W9JZxMBsYd9JFV8Si9aDh22k2BR/4m852vH7KGlrJeMpzhmyjDWOo0PJJM6yZsTeEpGkDHMHQ255+g=:"
              },
              {
                  "transport":"tcp",
                  "traddr":" 192.168.2.25 ",
                    "host_traddr":" 192.168.2.31",
                  "trsvcid":"4420",
                  "dhchap_ctrl_key":"DHHC-
                  1:03: wSpuuKbBHTzC0W9JZxMBsYd9JFV8Si9aDh22k2BR/4m852vH7KGlrJeMpzhmyjDWOo0PJJM6yZsTeEpGkDHMHQ255+g=:"
              }
          ]
      }
  ]
}
]

Connect to the ONTAP controller using the config JSON file:

nvme connect-all -J /etc/nvme/config.json

Show example

already connected to hostnqn=nqn.2014-08.org.nvmexpress:uuid:4c4c4544-0035-5910-804b-b5c04f444d33,nqn=nqn.1992-08.com.netapp:sn.8dde3be2cc7c11efb777d039eab6cb6d:subsystem. bidi
r_DHCP,transport=tcp,traddr=192.168.1.25,trsvcid=4420
already connected to hostnqn=nqn.2014-08.org.nvmexpress:uuid:4c4c4544-0035-5910-804b-b5c04f444d33,nqn=nqn.1992-08.com.netapp:sn.8dde3be2cc7c11efb777d039eab6cb6d:subsystem. bidi
r_DHCP,transport=tcp,traddr=192.168.2.25,trsvcid=4420
already connected to hostnqn=nqn.2014-08.org.nvmexpress:uuid:4c4c4544-0035-5910-804b-b5c04f444d33,nqn=nqn.1992-08.com.netapp:sn.8dde3be2cc7c11efb777d039eab6cb6d:subsystem. bidi
r_DHCP,transport=tcp,traddr=192.168.1.24,trsvcid=4420
already connected to hostnqn=nqn.2014-08.org.nvmexpress:uuid:4c4c4544-0035-5910-804b-b5c04f444d33,nqn=nqn.1992-08.com.netapp:sn.8dde3be2cc7c11efb777d039eab6cb6d:subsystem. bidi
r_DHCP,transport=tcp,traddr=192.168.2.24,trsvcid=4420

Verify that the dhchap secrets have been enabled for the respective controllers for each subsystem:

Verify the host dhchap keys:

cat /sys/class/nvme-subsystem/nvme-subsys0/nvme0/dhchap_secret

The following example shows a dhchap key:

DHHC-1:01:CNxTYq73T9vJk0JpOfDBZrhDCqpWBN4XVZI5WxwPgDUieHAi:

Verify the controller dhchap keys:

cat /sys/class/nvme-subsystem/nvme-subsys0/nvme0/dhchap_ctrl_secret

You should see output similar to the following example:

DHHC-1:03:wSpuuKbBHTzC0W9JZxMBsYd9JFV8Si9aDh22k2BR/4m852vH7KGlrJeMpzhmyjDWOo0PJJM6yZsTeEpGkDHMHQ255+g=:

Step 8: Review the known issues

There are no known issues.

Configure RHEL 9.6 for NVMe-oF with ONTAP storage

Creating your file...

Step 1: Optionally, enable SAN booting

Step 2: Verify the software version and NVMe configuration

Step 3: Configure NVMe/FC and NVMe/TCP

Modify the iopolicy in the udev rules

Step 4: Optionally, enable 1MB I/O for NVMe/FC

Step 5: Verify NVMe boot services

Step 6: Verify the multipathing configuration

Step 7: Set up secure in-band authentication

Step 8: Review the known issues