Replacing 7-Mode LUN WWIDs on Linux hosts after transition of LUNs
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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
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
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:
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:
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:
Configure the DMMP devices:
Verify that the DMMP alias is correctly referencing the ONTAP LUN WWID:
In the following sample output, the DMMP alias
3600a098051764b2d4f3f453135452d31as 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]