Skip to main content
SAN hosts and cloud clients

NVMe/FC Host Configuration for Oracle Linux 8.6 with ONTAP

Contributors netapp-ranuk netapp-pcarriga
PDFs

You can configure NVMe over Fibre Channel (NVMe/FC) on initiator hosts running Oracle Linux 8.6 and ONTAP as the target.

Supportability

NVMe over Fabrics or NVMe-oF (including NVMe/FC and NVMe/TCP) is supported with Oracle Linux 8.6 with Asymmetric Namespace Access (ANA) that 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. Using this procedure, you can enable NVMe-oF with in-kernel NVMe Multipath using ANA on Oracle Linux 8.6 and ONTAP as the target.

Note 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 8.6 has in-kernel NVMe multipath enabled by default for NVMe namepsaces.

  • With Oracle Linux 8.6, 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 8.6, a native udev rule is provided as part of the nvme-cli package which enables round-robin load balancing for NVMe multipath. Therefore, you need not manually create this rule anymore.

  • With Oracle Linux 8.6, 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 8.6, the NetApp plug-in 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 for exact details regarding supported configurations.

Enable NVMe/FC with Oracle Linux 8.6

Steps

  1. Install Oracle Linux 8.6 GA on the server. After the installation is complete, verify that you are running the specified Oracle Linux 8.6 GA kernel. See the NetApp Interoperability Matrix for the most current list of supported versions.

    # uname -r
5.4.17-2136.307.3.1.el8uek.x86_64

  2. Install the nvme-cli package:

    # rpm -qa|grep nvme-cli
nvme-cli-1.14-3.el8.x86_64

  3. On the Oracle Linux 8.6 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:4c4c4544-0032-3310-8033-b8c04f4c5132
::> vserver nvme subsystem host show -vserver vs_ol_nvme
Vserver     Subsystem          Host NQN
----------- --------------- ----------------------------------------------------------
vs_ol_nvme  nvme_ss_ol_1    nqn.2014-08.org.nvmexpress:uuid:9ed5b327-b9fc-4cf5-97b3-1b5d986345d1
    Note 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:

  4. Reboot the host.

    Note

    If you intend to run both NVMe and SCSI traffic on the same Oracle Linux 8.6 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.

Configure Broadcom FC adapter for NVMe/FC

Steps

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

    # 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

  2. 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:

    # 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
0:12.8.0.11

  3. Verify that lpfc_enable_fc4_type is set to 3:

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

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

    # cat /sys/class/fc_host/host*/port_name
0x100000109b1c1204
0x100000109b1c1205
# cat /sys/class/fc_host/host*/port_state
Online
Online
# cat /sys/class/scsi_host/host*/nvme_info
NVME Initiator Enabled
XRI Dist lpfc0 Total 6144 IO 5894 ELS 250
NVME LPORT lpfc0 WWPN x100000109b1c1204 WWNN x200000109b1c1204 DID x011d00 ONLINE
NVME RPORT WWPN x203800a098dfdd91 WWNN x203700a098dfdd91 DID x010c07 TARGET DISCSRVC ONLINE
NVME RPORT WWPN x203900a098dfdd91 WWNN x203700a098dfdd91 DID x011507 TARGET DISCSRVC ONLINE
NVME Statistics
LS: Xmt 0000000f78 Cmpl 0000000f78 Abort 00000000
LS XMIT: Err 00000000 CMPL: xb 00000000 Err 00000000
Total FCP Cmpl 000000002fe29bba Issue 000000002fe29bc4 OutIO 000000000000000a
abort 00001bc7 noxri 00000000 nondlp 00000000 qdepth 00000000 wqerr 00000000 err 00000000
FCP CMPL: xb 00001e15 Err 0000d906
NVME Initiator Enabled
XRI Dist lpfc1 Total 6144 IO 5894 ELS 250
NVME LPORT lpfc1 WWPN x100000109b1c1205 WWNN x200000109b1c1205 DID x011900 ONLINE
NVME RPORT WWPN x203d00a098dfdd91 WWNN x203700a098dfdd91 DID x010007 TARGET DISCSRVC ONLINE
NVME RPORT WWPN x203a00a098dfdd91 WWNN x203700a098dfdd91 DID x012a07 TARGET DISCSRVC ONLINE
NVME Statistics
LS: Xmt 0000000fa8 Cmpl 0000000fa8 Abort 00000000
LS XMIT: Err 00000000 CMPL: xb 00000000 Err 00000000
Total FCP Cmpl 000000002e14f170 Issue 000000002e14f17a OutIO 000000000000000a
abort 000016bb noxri 00000000 nondlp 00000000 qdepth 00000000 wqerr 00000000 err 00000000
FCP CMPL: xb 00001f50 Err 0000d9f8

Enable 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.

Note The following steps don't apply to Qlogic NVMe/FC hosts.
Steps

  1. Set the lpfc_sg_seg_cnt parameter to 256:

    cat /etc/modprobe.d/lpfc.conf
    Example output
    options lpfc lpfc_sg_seg_cnt=256

  2. Run the dracut -f command, and reboot the host:

  3. 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 8.6 GA kernel has the latest upstream fixes. These fixes are essential for ONTAP support.

Steps

  1. 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:v10.02.00.106-k
QLE2742 FW:v9.08.02 DVR:v10.02.00.106-k

  2. Verify that ql2xnvmeenable 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

  1. Verify that the initiator port can fetch the 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
...

  2. Similarly, verify that the 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

  3. Now run the nvme connect-all command across all the supported NVMe/TCP initiator-target LIFs across the nodes. MAke sure you pass a longer ctrl_loss_tmo period (such as, say 30 minutes, which can be set through -l 1800) during the connect-all so that it would retry for a longer period in the event of a path loss. For 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

  1. Verify the following NVMe/FC settings on the Oracle Linux 8.6 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

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

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


Namespace Usage    Format             FW             Rev
-----------------------------------------------------------
1                 85.90 GB / 85.90 GB  4 KiB + 0 B   FFFFFFFF
2                 85.90 GB / 85.90 GB  24 KiB + 0 B  FFFFFFFF
3                 85.90 GB / 85.90 GB  4 KiB + 0 B   FFFFFFFF

  3. 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 inaccessible
+- nvme1 fc traddr=nn-0x203700a098dfdd91:pn-0x203900a098dfdd91 host_traddr=nn-0x200000109b1c1204:pn-0x100000109b1c1204 live inaccessible
+- 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

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

    # 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 8.6 with ONTAP has the following known issues:

NetApp Bug ID Title Description

1517321

Oracle Linux 8.6 NVMe-oF Hosts create duplicate Persistent Discovery Controllers

On Oracle Linux 8.6 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 8.6 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.