# sanlun lun show all

controller(7mode/E-Series)/            device     host               lun
vserver(cDOT/FlashRay)   lun-pathname  filename   adapter  protocol  size    Product
------------------------------------------------------------------------------------
data_vserver          /vol/vol1/lun1   /dev/sdb   host16   FCP       120.0g  cDOT
data_vserver          /vol/vol1/lun1   /dev/sdc   host15   FCP       120.0g  cDOT
data_vserver          /vol/vol2/lun2   /dev/sdd   host16   FCP       120.0g  cDOT
data_vserver          /vol/vol2/lun2   /dev/sde   host15   FCP       120.0g  cDOT

chkconfig multipathd on
/etc/init.d/multipathd start

blacklist {
        wwid <DevId>
        devnode "^(ram|raw|loop|fd|md|dm-|sr|scd|st)[0-9]*"
        devnode "^hd[a-z]"
        devnode "^cciss.*"
}

+
`sda` is the local SCSI disk that you want to add to the blacklist.

. Add the `WWID` to the blacklist stanza in `/etc/multipath.conf`:
[source,cli]
+

Always check your `/etc/multipath.conf` file, especially in the defaults section, for legacy settings that might be overriding default settings.

The following table demonstrates the critical `multipathd` parameters for ONTAP LUNs and the required values. If a host is connected to LUNs from other vendors and any of these parameters are overridden, they must be corrected by later stanzas in the `multipath.conf` file that apply specifically to ONTAP LUNs. Without this correction, the ONTAP LUNs might not work as expected. You should only override these defaults in consultation with NetApp, the OS vendor, or both, and only when the impact is fully understood.

//ONTAPDOC-2578 9-Dec-2024
//ONTAPDOC-2561 25-Nov-202


[cols=2*,options="header"]
|===
| Parameter
| Setting
| detect_prio | yes
| dev_loss_tmo | "infinity"
| failback | immediate
| fast_io_fail_tmo | 5
| features | "2 pg_init_retries 50"
| flush_on_last_del | "yes"
| hardware_handler | "0"
| no_path_retry | queue
| path_checker | "tur"
| path_grouping_policy | "group_by_prio"
| path_selector | "service-time 0"
| polling_interval | 5
| prio | "ontap"
| product | LUN.*
| retain_attached_hw_handler | yes
| rr_weight | "uniform"
| user_friendly_names | no
| vendor | NETAPP
|===

.Example

The following example shows how to correct an overridden default. In this case, the `multipath.conf` file defines values for `path_checker` and `no_path_retry` that are not compatible with ONTAP LUNs. If they cannot be removed because of other SAN arrays still attached to the host, these parameters can be corrected specifically for ONTAP LUNs with a device stanza.

== Known issues

The SUSE Linux Enterprise Server 15 SP3 with ONTAP release has the following known issues:

[cols=3*,options="header"]
|===
| NetApp Bug ID
| Title
| Description
| link:https://mysupport.netapp.com/NOW/cgi-bin/bol?Type=Detail&Display=1089555[1089555^] | Kernel disruption observed on kernel version SLES12 SP3 with Emulex LPe16002 16GB FC during storage failover operation | A kernel disruption might occur during storage failover operations on kernel version SLES12 SP3 with Emulex LPe16002 HBA. The kernel disruption prompts a reboot of the operating system, which in turn causes an application disruption. If the kdump is configured, the kernel disruption generates a vmcore file under /var/crash/directory. You can investigate the cause of the failure in the vmcore file.
Example:
In the observed case, the kernel disruption was observed in the module “lpfc_sli_ringtxcmpl_put+51” and is logged in the vmcore file
– exception RIP: lpfc_sli_ringtxcmpl_put+51.

Recover the operating system after the kernel disruption by rebooting the host operating system and restarting the application.
| link:https://mysupport.netapp.com/NOW/cgi-bin/bol?Type=Detail&Display=1089561[1089561^] | Kernel disruption observed on kernel version SLES12 SP3 with Emulex LPe32002 32GB FC during storage failover operations | A kernel disruption might occur during storage failover operations on kernel version SLES12 SP3 with Emulex LPe32002 HBA. The kernel disruption prompts a reboot of the operating system, which in turn causes an application disruption. If the kdump is configured, the kernel disruption generates a vmcore file under /var/crash/directory. You can investigate the cause of the failure in the vmcore file.
Example:
In the observed case, the kernel disruption was observed in the module
“lpfc_sli_free_hbq+76” and is logged in the vmcore file
– exception RIP: lpfc_sli_free_hbq+76.

Recover the operating system after the kernel disruption by rebooting the host operating system and restarting the application.
| link:https://mysupport.netapp.com/NOW/cgi-bin/bol?Type=Detail&Display=1117248[1117248^] | Kernel disruption observed on SLES12SP3 with QLogic QLE2562 8GB FC during storage failover operations |  During storage failover operations on the Sles12sp3 kernel (kernel-default-4.4.82-6.3.1) with QLogic QLE2562 HBA, the kernel disruption was observed due to a panic in the kernel. The kernel panic leads to a reboot of the operating system, causing an application disruption. The kernel panic generates the vmcore file under the /var/crash/ directory if kdump is configured. Upon the kernel panic, the vmcore file can be used to understand the cause of the failure.
Example:
In this case, the panic was observed in the “blk_finish_request+289” module.
It is logged in the vmcore file with the following string:
"exception RIP: blk_finish_request+289"

After the kernel disruption, you can recover the operating system  by rebooting the Host OS. You can restart the application as required.
| link:https://mysupport.netapp.com/NOW/cgi-bin/bol?Type=Detail&Display=1117261[1117261^] | Kernel disruption observed on SLES12SP3 with Qlogic QLE2662 16GB FC during storage failover operations | During storage failover operations on Sles12sp3 kernel (kernel-default-4.4.82-6.3.1) with Qlogic QLE2662 HBA, you might observe kernel disruption. This prompts a reboot of the operating system causing application disruption. The kernel disruption generates a vmcore file under /var/crash/ directory if kdump is configured. The vmcore file can be used to understand the cause of the failure.
Example:
In this case the Kernel disruption was observed in the module "unknown or invalid address" and is logged in vmcore file with the following string - exception RIP: unknown or invalid address.

After kernel disruption, the operating system can be recovered by rebooting the host operating system and restarting the application as required.
| link:https://mysupport.netapp.com/NOW/cgi-bin/bol?Type=Detail&Display=1117274[1117274^] | Kernel disruption observed on SLES12SP3 with Emulex LPe16002 16GB FC during storage failover operations | During storage failover operations on Sles12sp3 kernel (kernel-default-4.4.87-3.1) with Emulex LPe16002 HBA, you might observe kernel disruption. This prompts a reboot of the operating system causing application disruption. The kernel disruption
generates a vmcore file under the /var/crash/ directory if kdump is configured. The vmcore file can be used to understand the cause
of the failure.
Example:
In this case kernel disruption was observed in the module “raw_spin_lock_irqsave+30” and is logged in the vmcore file with the following string:
– exception RIP: _raw_spin_lock_irqsave+30.

After kernel disruption, the operating system can be recovered by rebooting the host operating system and restarting the application as required.
|===

// 2024 SEP 2, ONTAPDOC-2345