NVMe/FC Host Configuration for Oracle Linux 8.4 with ONTAP

10/29/2024 Contributors

You can configure NVMe over Fibre Channel (NVMe/FC) on initiator hosts running Oracle Linux 8.4 and ONTAP as the target.

Supportability

NVMe over Fabrics or NVMe-oF (including NVMe/FC and NVMe/TCP) is supported with Oracle Linux 8.4 with Asymmetric Namespace Access (ANA), which is required for surviving storage failovers (SFOs) on the ONTAP array. ANA is the asymmetric logical unit access (ALUA) equivalent in the NVMe-oF environment, and is currently implemented with in-kernel NVMe Multipath. This topic details how to enable NVMe-oF with in-kernel NVMe Multipath using ANA on Oracle Linux 8.4 with ONTAP as the target.

You can use the configuration settings provided in this document to configure cloud clients connected to Cloud Volumes ONTAP and Amazon FSx for ONTAP.

Features

Oracle Linux 8.4 has in-kernel NVMe multipath enabled by default for NVMe namepsaces.
With Oracle Linux 8.4, nvme-fc auto-connect scripts are included in the native nvme-cli package. You can use these native auto-connect scripts instead of installing external vendor provided outbox auto-connect scripts.
With Oracle Linux 8.4, a native udev rule is provided as part of the nvme-cli package which enables round-robin load balancing for NVMe multipath. Therefore, you do not need to manually create this rule anymore.
With Oracle Linux 8.4, both NVMe and SCSI traffic can be run on the same co-existent host. In fact, that is expected to be the commonly deployed host configuration. Therefore, you can configure dm-multipath as usual for SCSI LUNs resulting in mpath devices whereas NVMe multipath can be used to configure NVMe-oF multipath devices (for example, /dev/nvmeXnY) on the host.
With Oracle Linux 8.4, the NetApp plugin in the native nvme-cli package is capable of displaying ONTAP details as well as ONTAP namespaces.

Known limitations

SAN booting using the NVMe-oF protocol is currently not supported.

Configuration requirements

Refer to the NetApp Interoperability Matrix (IMT) for exact details on supported configurations.

Enable NVMe/FC

Steps

Install Oracle Linux 8.4 GA on the server. After the installation is complete, verify that you are running the specified Oracle Linux 8.4 GA kernel. See the NetApp Interoperability Matrix for the most current list of supported versions.
```
# uname -r
5.4.17-2102.206.1.el8uek.x86_64
```

Install the nvme-cli package.

# rpm -qa|grep nvme-cli
nvme-cli-1.12-3.el8.x86_64

On the Oracle Linux 8.4 host, check the hostnqn string at /etc/nvme/hostnqn and verify that it matches the hostnqn string for the corresponding subsystem on the ONTAP array.

# cat /etc/nvme/hostnqn
nqn.2014-08.org.nvmexpress:uuid:8b43c7c6-e98d-4cc7-a699-d66a69aa714e
::> vserver nvme subsystem host show -vserver vs_coexistance_2

Vserver         Subsystem Host NQN
------- --------------------------------------------------------------------
vs_coexistance_2 nvme_1   nqn.2014-08.org.nvmexpress:uuid:753881b6-3163-46f9-8145-0d1653d99389

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

Reboot the host.

If you intend to run both NVMe and SCSI traffic on the same Oracle Linux 8.4 co-existent host, NetApp recommends using the in-kernel NVMe multipath for ONTAP namespaces and dm-multipath for ONTAP LUNs respectively. This also means the ONTAP namespaces should be blacklisted in dm-multipath to prevent dm-multipath from claiming these namespace devices. This can be done by adding the enable_foreign setting to the /etc/multipath.conf file:

#cat /etc/multipath.conf
defaults {
    enable_foreign  NONE
}

Restart the multipathd daemon by running the systemctl restart multipathd command to let the new setting take effect.

Configuring the Broadcom FC adapter for NVMe/FC

Steps

Verify that you are using the supported adapter. For the most current list of supported adapters, see the NetApp Interoperability Matrix Tool.

# cat /sys/class/scsi_host/host*/modelname
LPe32002-M2
LPe32002-M2

# cat /sys/class/scsi_host/host*/modeldesc
Emulex LightPulse LPe32002-M2 2-Port 32Gb Fibre Channel Adapter
Emulex LightPulse LPe32002-M2 2-Port 32Gb Fibre Channel Adapter

Verify that you are using the recommended Broadcom lpfc firmware and inbox driver. For the most current list of supported adapter driver and firmware versions, see the NetApp Interoperability Matrix Tool.
```
# cat /sys/class/scsi_host/host*/fwrev
14.0.505.11, sli-4:2:c
14.0.505.11, sli-4:2:c
```
```
# cat /sys/module/lpfc/version
0:12.8.0.5
```

Verify that lpfc_enable_fc4_type is set to 3.

# cat /sys/module/lpfc/parameters/lpfc_enable_fc4_type
3

Verify that the initiator ports are up and running, and you can see the target LIFs.

# cat /sys/class/fc_host/host*/port_name
0x100000109b213a00
0x100000109b2139ff

# cat /sys/class/fc_host/host*/port_state
Online
Online

# cat /sys/class/scsi_host/host*/nvme_info
NVME Initiator Enabled
XRI Dist lpfc1 Total 6144 IO 5894 ELS 250
NVME LPORT lpfc1 WWPN x100000109b213a00 WWNN x200000109b213a00 DID x031700     ONLINE
NVME RPORT WWPN x208cd039ea243510 WWNN x208bd039ea243510 DID x03180a TARGET DISCSRVC ONLINE
NVME RPORT WWPN x2090d039ea243510 WWNN x208bd039ea243510 DID x03140a TARGET DISCSRVC ONLINE

NVME Statistics
LS: Xmt 000000000e Cmpl 000000000e Abort 00000000
LS XMIT: Err 00000000 CMPL: xb 00000000 Err 00000000
Total FCP Cmpl 0000000000079efc Issue 0000000000079eeb OutIO ffffffffffffffef
abort 00000002 noxri 00000000 nondlp 00000000 qdepth 00000000 wqerr 00000000 err   00000000
FCP CMPL: xb 00000002 Err 00000004

NVME Initiator Enabled
XRI Dist lpfc0 Total 6144 IO 5894 ELS 250
NVME LPORT lpfc0 WWPN x100000109b2139ff WWNN x200000109b2139ff DID x031300 ONLINE
NVME RPORT WWPN x208ed039ea243510 WWNN x208bd039ea243510 DID x03230c TARGET DISCSRVC ONLINE
NVME RPORT WWPN x2092d039ea243510 WWNN x208bd039ea243510 DID x03120c TARGET DISCSRVC ONLINE

NVME Statistics
LS: Xmt 000000000e Cmpl 000000000e Abort 00000000
LS XMIT: Err 00000000 CMPL: xb 00000000 Err 00000000
Total FCP Cmpl 0000000000029ba0 Issue 0000000000029ba2 OutIO 0000000000000002
abort 00000002 noxri 00000000 nondlp 00000000 qdepth 00000000 wqerr 00000000 err 00000000
FCP CMPL: xb 00000002 Err 00000004

Enabling 1MB I/O size

ONTAP reports an MDTS (Max Data Transfer Size) 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 1 MB for a Broadcom NVMe/FC host, you must increase the lpfc value of the lpfc_sg_seg_cnt parameter to 256 from the default value of 64.

The following 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

Example output

options lpfc lpfc_sg_seg_cnt=256

Run the dracut -f command, and reboot the host:
Verify that lpfc_sg_seg_cnt is 256:
```
cat /sys/module/lpfc/parameters/lpfc_sg_seg_cnt
```
The expected value is 256.

Configure the Marvell/QLogic FC adapter for NVMe/FC

The native inbox qla2xxx driver included in the OL 8.4 GA kernel has the latest upstream fixes. These fixes are essential for ONTAP support.

Steps

Verify that you are running the supported adapter driver and firmware versions:

# cat /sys/class/fc_host/host*/symbolic_name
QLE2742 FW:v9.08.02 DVR:v10.02.00.103-k
QLE2742 FW:v9.08.02 DVR:v10.02.00.103-k

Verify that the ql2xnvmeenable parameter is set which enables the Marvell adapter to function as an NVMe/FC initiator.
```
# cat /sys/module/qla2xxx/parameters/ql2xnvmeenable
1
```

Configure NVMe/TCP

NVMe/TCP does not have auto-connect functionality. Therefore, if a path goes down and is not reinstated within the default time out period of 10 minutes, NVMe/TCP cannot automatically reconnect. To prevent a time out, you should set the retry period for failover events to at least 30 minutes.

Steps

Verify that the initiator port is able to fetch discovery log page data across the supported NVMe/TCP LIFs:

# nvme discover -t tcp -w 192.168.1.8 -a 192.168.1.51
Discovery Log Number of Records 10, Generation counter 119
=====Discovery Log Entry 0======
trtype: tcp
adrfam: ipv4
subtype: nvme subsystem
treq: not specified
portid: 0
trsvcid: 4420
subnqn: nqn.1992-08.com.netapp:sn.56e362e9bb4f11ebbaded039ea165abc:subsystem.nvme_118_tcp_1
traddr: 192.168.2.56
sectype: none
=====Discovery Log Entry 1======
trtype: tcp
adrfam: ipv4
subtype: nvme subsystem
treq: not specified
portid: 1
trsvcid: 4420
subnqn: nqn.1992-08.com.netapp:sn.56e362e9bb4f11ebbaded039ea165abc:subsystem.nvme_118_tcp_1
traddr: 192.168.1.51
sectype: none
=====Discovery Log Entry 2======
trtype: tcp
adrfam: ipv4
subtype: nvme subsystem
treq: not specified
portid: 0
trsvcid: 4420
subnqn: nqn.1992-08.com.netapp:sn.56e362e9bb4f11ebbaded039ea165abc:subsystem.nvme_118_tcp_2
traddr: 192.168.2.56
sectype: none
...

Similarly, verify that other NVMe/TCP initiator-target LIF combinations are able to successfully fetch discovery log page data.
Example,

# nvme discover -t tcp -w 192.168.1.8 -a 192.168.1.51
#nvme discover -t tcp -w 192.168.1.8 -a 192.168.1.52
# nvme discover -t tcp -w 192.168.2.9 -a 192.168.2.56
# nvme discover -t tcp -w 192.168.2.9 -a 192.168.2.57

Now run the nvme connect-all command across all the supported NVMe/TCP initiator-target LIFs across the nodes. Make sure you provide a longer ctrl_loss_tmo timer period (30 minutes or more, which can be set adding -l 1800) during connect-all so that it would retry for a longer period in the event of a path loss.
Example:
```
# nvme connect-all -t tcp -w 192.168.1.8 -a 192.168.1.51 -l 1800
# nvme connect-all -t tcp -w 192.168.1.8 -a 192.168.1.52 -l 1800
# nvme connect-all -t tcp -w 192.168.2.9 -a 192.168.2.56 -l 1800
# nvme connect-all -t tcp -w 192.168.2.9 -a 192.168.2.57 -l 1800
```

Validate NVMe/FC

Steps

Verify the following NVMe/FC settings on the Oracle Linux 8.4 host:

# cat /sys/module/nvme_core/parameters/multipath
Y

# cat /sys/class/nvme-subsystem/nvme-subsys*/model
NetApp ONTAP Controller
NetApp ONTAP Controller

# cat /sys/class/nvme-subsystem/nvme-subsys*/iopolicy
round-robin
round-robin

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

# nvme list
Node                  SN              Model                                   Namespace
-----------------------------------------------------------------------------------------
/dev/nvme0n1     814vWBNRwf9HAAAAAAAB  NetApp ONTAP Controller                1
/dev/nvme0n2     814vWBNRwf9HAAAAAAAB  NetApp ONTAP Controller                2
/dev/nvme0n3     814vWBNRwf9HAAAAAAAB  NetApp ONTAP Controller                3

Usage      Format         FW Rev
------------------------------------------------------
85.90 GB / 85.90 GB     4 KiB + 0 B   FFFFFFFF
85.90 GB / 85.90 GB     4 KiB + 0 B   FFFFFFFF
85.90 GB / 85.90 GB     4 KiB + 0 B   FFFFFFFF

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

# nvme list-subsys /dev/nvme0n1
nvme-subsys0 - NQN=nqn.1992-08.com.netapp:sn.5f5f2c4aa73b11e9967e00a098df41bd:subsystem.nvme_ss_ol_1
\
+- nvme0 fc traddr=nn-0x203700a098dfdd91:pn-0x203800a098dfdd91 host_traddr=nn-0x200000109b1c1204:pn-0x100000109b1c1204 live non-optimized
+- nvme1 fc traddr=nn-0x203700a098dfdd91:pn-0x203900a098dfdd91 host_traddr=nn-0x200000109b1c1204:pn-0x100000109b1c1204 live non-optimized
+- nvme2 fc traddr=nn-0x203700a098dfdd91:pn-0x203a00a098dfdd91 host_traddr=nn-0x200000109b1c1205:pn-0x100000109b1c1205 live optimized
+- nvme3 fc traddr=nn-0x203700a098dfdd91:pn-0x203d00a098dfdd91 host_traddr=nn-0x200000109b1c1205:pn-0x100000109b1c1205 live optimized

Verify that the NetApp plug-in displays correct values for each ONTAP namespace devices.

# nvme netapp ontapdevices -o column
Device                 Vserver          Namespace Path
----------------------- ------------------------------ ----------------------------------------------------------------------- --------- --
/dev/nvme0n1      vs_ol_nvme            /vol/ol_nvme_vol_1_1_0/ol_nvme_ns
/dev/nvme0n2      vs_ol_nvme            /vol/ol_nvme_vol_1_0_0/ol_nvme_ns
/dev/nvme0n3      vs_ol_nvme            /vol/ol_nvme_vol_1_1_1/ol_nvme_ns

NSID        UUID                                  Size
--------------------------------------------------------------
1          72b887b1-5fb6-47b8-be0b-33326e2542e2   85.90GB
2          04bf9f6e-9031-40ea-99c7-a1a61b2d7d08   85.90GB
3          264823b1-8e03-4155-80dd-e904237014a4   85.90GB

# nvme netapp ontapdevices -o json
{
"ONTAPdevices" : [
    {
        "Device" : "/dev/nvme0n1",
        "Vserver" : "vs_ol_nvme",
        "Namespace_Path" : "/vol/ol_nvme_vol_1_1_0/ol_nvme_ns",
        "NSID" : 1,
        "UUID" : "72b887b1-5fb6-47b8-be0b-33326e2542e2",
        "Size" : "85.90GB",
        "LBA_Data_Size" : 4096,
        "Namespace_Size" : 20971520
    },
    {
        "Device" : "/dev/nvme0n2",
        "Vserver" : "vs_ol_nvme",
        "Namespace_Path" : "/vol/ol_nvme_vol_1_0_0/ol_nvme_ns",
        "NSID" : 2,
        "UUID" : "04bf9f6e-9031-40ea-99c7-a1a61b2d7d08",
        "Size" : "85.90GB",
        "LBA_Data_Size" : 4096,
        "Namespace_Size" : 20971520
      },
      {
         "Device" : "/dev/nvme0n3",
         "Vserver" : "vs_ol_nvme",
         "Namespace_Path" : "/vol/ol_nvme_vol_1_1_1/ol_nvme_ns",
         "NSID" : 3,
         "UUID" : "264823b1-8e03-4155-80dd-e904237014a4",
         "Size" : "85.90GB",
         "LBA_Data_Size" : 4096,
         "Namespace_Size" : 20971520
       },
  ]
}

Known issues

The NVMe-oF host configuration for OL 8.4 with ONTAP has the following known issues:

NetApp Bug ID	Title	Description
1517321	Oracle Linux 8.4 NVMe-oF hosts create duplicate Persistent Discovery Controllers	On Oracle Linux 8.4 NVMe over Fabrics (NVMe-oF) hosts, you can use the "nvme discover -p" command to create Persistent Discovery Controllers (PDCs). When this command is used, only one PDC should be created per initiator-target combination. However, if you are running ONTAP 9.10.1 and Oracle Linux 8.4 with an NVMe-oF host, a duplicate PDC is created each time "nvme discover -p" is executed. This leads to unnecessary usage of resources on both the host and the target.

NetApp Bug ID

Title

Description

1517321

Oracle Linux 8.4 NVMe-oF hosts create duplicate Persistent Discovery Controllers

On Oracle Linux 8.4 NVMe over Fabrics (NVMe-oF) hosts, you can use the "nvme discover -p" command to create Persistent Discovery Controllers (PDCs). When this command is used, only one PDC should be created per initiator-target combination. However, if you are running ONTAP 9.10.1 and Oracle Linux 8.4 with an NVMe-oF host, a duplicate PDC is created each time "nvme discover -p" is executed. This leads to unnecessary usage of resources on both the host and the target.

NVMe/FC Host Configuration for Oracle Linux 8.4 with ONTAP

Creating your file...

Supportability

Features

Known limitations

Configuration requirements

Enable NVMe/FC

Configuring the Broadcom FC adapter for NVMe/FC

Enabling 1MB I/O size

Configure the Marvell/QLogic FC adapter for NVMe/FC

Configure NVMe/TCP

Validate NVMe/FC

Known issues