Replacing 7-Mode LUN WWIDs on Linux hosts after transition of LUNs
After LUN transition, the 7-Mode LUN WWID changes. You must replace it with the corresponding ONTAP LUN WWID before you can begin servicing data.
If you are doing a copy-free transition (CFT), then procedures for vol rehost must be complete.
See the 7-Mode Transition Tool Copy-Free Transition Guidefor details.
-
For copy-based transitions (CBTs), perform these steps after completing the Storage cutover operation in the 7MTT.
-
For CFTs, perform these steps after the Import Data & Configuration operation in the 7MTT is complete.
-
Generate the 7-Mode to ONTAP LUN mapping file:
-
For CBTs, run the following command from the Linux host where the 7MTT is installed:
transition cbt export lunmap -p project-name -o file_path
For example:
transition cbt export lunmap -p SanWorkLoad -o c:/Libraires/Documents/7-to-C-LUN-MAPPING.csv
-
For CFTs, run the following command from the system where the 7MTT is installed:
transition cft export lunmap -p project-name -s svm-name -o output-file
For example:
transition cft export lunmap -p SanWorkLoad -s svml -0 c:/Libraries/Documents/7-to-C-LUN-MAPPING-svml.csv
You must run this command for each of your storage virtual machines (SVMs).
-
-
Make a note of the new ONTAP LUN device handle ID from the LUN mapping file.
-
Remove the SCSI devices created for 7-Mode LUNs:
-
To remove all of the SCSI devices:
rescan-scsi-bus.sh -r
-
To remove each SCSI device individually:
echo 1> /sys/block/SCSI_ID/delete
This command must be executed on all 7-Mode LUN SCSI devices. See the SCSI Device ID column on the SAN Host LUNs tab of the Inventory Assessment Workbook to identify the SCSI device IDs for the LUNs.
-
-
Discover new ONTAP LUNs:
rescan-scsi-bus.sh
-
Identify the SCSI devices of the new ONTAP LUNs:
sanlun lun show
-
Get the WWIDs for the new ONTAP LUNs:
/lib/udev/scsi_id -g -u -d /dev SCSI_dev
-
If a DMMP alias is defined, then update the /etc/multipath.conf file to replace the 7-Mode LUN WWID with its corresponding ONTAP LUN WWID, so that the DMMP alias points to the clustered Data ONTAP LUN:
cat /etc/multipath.conf
-
Configure the DMMP devices:
multipath
-
Verify that the DMMP alias is correctly referencing the ONTAP LUN WWID:
multipath -11
In the following sample output, the DMMP alias
dmmp_raw_lun
is referencing3600a098051764b2d4f3f453135452d31
as the ONTAP WWID:root@IBMx3550M3-229-169 ~]# multipath -ll dmmp_raw_lun dmmp_raw_lun (3600a098051764b2d4f3f453135452d31) dm-8 NETAPP, LUN C-Mode [size=1.0G] [features=3 queue_if_no_path pg_init_retries 50] [hwhandler=1 alua] [rw] \_round-robin 0 [prio=50][enabled] \_5:0:0:6 sdx 65:112 [active][ready] \_8:0:0:6 sdab 65:176 [active][ready] \_round-robin 0 [prio=10][enabled] \_6:0:0:6 sdy 65:128 [active][ready] \_7:0:0:6 sdaa 65:160 [active][ready]