# 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 | "3 queue_if_no_path 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.

=== Configure KVM settings

You can use the recommended settings to configure Kernel-based Virtual Machine (KVM) as well. There are no changes required to configure KVM because the LUN is mapped to the hypervisor.

//ONTAPDOC-2561 5-Dec-2024

== Known issues

The RHEL 7.0 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=844417[844417^] | Emulex 16G FC (LPe16002B-M6) host crashes during I/O with storage failover operations | You might observe a 16G FC Emulex (LPe16002B-M6) host crash during I/O with storage failover operations.
| link:https://mysupport.netapp.com/NOW/cgi-bin/bol?Type=Detail&Display=811587[811587^] | Emulex 16G FC (LPe16002B-M6) host crashes during I/O with storage failover operations | You might observe a 16G FC Emulex (LPe16002B-M6) host crash during I/O with storage failover operations.
| link:https://mysupport.netapp.com/NOW/cgi-bin/bol?Type=Detail&Display=803071[803071^] | Emulex 16G FC (LPe16002B-M6) host crashes during I/O with storage failover operations | You might observe a 16G FC Emulex (LPe16002B-M6) host crash during I/O with storage failover operations.
| link:https://mysupport.netapp.com/NOW/cgi-bin/bol?Type=Detail&Display=820163[820163^] | QLogic host hang or path failures observed during I/O with storage failover operations | You might observe a host hang or path failures on QLogic host during I/O with storage failover operations. In such scenarios, you might see the following message: "Mailbox cmd timeout occurred, cmd=0x54, mb[0]=0x54 and Firmware dump saved to temp buffer" messages which leads to host hung/path failure.
| link:https://mysupport.netapp.com/NOW/cgi-bin/bol?Type=Detail&Display=799323[799323^] | Emulex FCoE (OCe10102-FX-D) host hang or path failures observed during I/O with storage failover operations | You might observe a host hang or path failures on Emulex 10G FCoE host (OCe10102-FX-D) during I/O with storage failover operations. In such scenarios, you might see the following message:  "driver's buffer pool is empty, IO busied and SCSI Layer I/O Abort Request Status" messages which leads to host hung/path failures.
| link:https://mysupport.netapp.com/NOW/cgi-bin/bol?Type=Detail&Display=849212[849212^] | Emulex 16G FC (LPe16002B-M6) host hang or path failures are observed during I/O with storage failover operations | You might observe a host hang or path failures on Emulex 16G FC (LPe16002B-M6) host during I/O with storage failover operations. In such scenarios, you might see the following message:  "RSCN timeout Data and iotag x1301 is out of range: max iotag" messages which leads to host hung/path failures.
| link:https://mysupport.netapp.com/NOW/cgi-bin/bol?Type=Detail&Display=836800[836800^] | Anaconda displays an iSCSI login failure message although logins are successful during RHEL 7.0 OS installation | When you install the root(/) on a iSCSI multipath’d LUN, the IP address for the  Ethernet interfaces are specified in the kernel command line so that the IP addresses are assigned before the iSCSI service starts. However, dracut cannot assign IP addresses to all the Ethernet ports during the boot, before the iSCSI service starts. This causes the iSCSI login to fail on interfaces without IP addresses. You will see the iSCSI service attempt to login numerous times,  which will cause a delay in the OS boot time.
| link:https://mysupport.netapp.com/NOW/cgi-bin/bol?Type=Detail&Display=836875[836875^] | IP addresses are not always assigned during the boot of a RHEL 7.0 OS installed on an iSCSI multipath'd LUN | When you are installing RHEL 7.0, the anaconda installation screen displays that iSCSI login to multiple target IPs have failed though the iSCSI logins are successful. Anaconda displays following error message: “Node Login Failed” You will observe this error only when you select multiple target IPs for iSCSI login. You can continue the OS installation by clicking the "ok" button. This bug does not hamper either the iSCSI or the RHEL 7.0 OS installation.
| link:https://mysupport.netapp.com/NOW/cgi-bin/bol?Type=Detail&Display=836657[836657^] | Anaconda does not add bootdev argument in kernel cmd line to set IP address for RHEL 7.0 OS installed on iSCSI multipath'd LUN | Anaconda does not add a bootdev argument in the kernel command line where you set the IPv4 address during the RHEL 7.0 OS installation on an iSCSI multipath'd LUN. This prevents assigning of IP addresses to any of the Ethernet interfaces that were configured to establish iSCSI sessions with the storage subsystem during the RHEL 7.0 boot. Since iSCSI sessions are not established, the root LUN is not discovered when the OS boots and hence the OS boot fails.
|===

// 2024 SEP 2, ONTAPDOC-2345