ONTAP Supports Converting LUN to Namespace and Namespace to LUN. And this conversion can be done w/o any data loss. So for a use where someone wanted to migrate Data from SCSI (Fibre Channel and iSCSI) to NVMe (NVMe-FC and NVMe-TCP) then it is possible and these are the steps,
- Pause the IO to the LUN or Namespace which needs to be converted.
- Unmap the LUN or Namespace from the iGroup or Subsystem respectively.
- Create the necessary LIFs (SCSI-FC , iSCSI , NVMe-FC or NVMe-TCP)
- Ensure the connectivity from the Hosts and Check if the initiators is logged in.
- Create iGroup or Subsystem.
- Convert Namespace to LUN or LUN to Namespace , can use the below commands for the conversion.
=========== Converting LUN to NS ===========
ONTAPCluster::*> lun show -volume NS2LUN2NSVolume
Vserver Path State Mapped Type Size
-------- ------------------------------- ------- -------- -------- --------
VServerNS2LUN2NS /vol/NS2LUN2NSVolume/Lun2NS online unmapped linux 40MB
ONTAPCluster::*> vserver nvme namespace convert-from-lun -lun-path /vol/NS2LUN2NSVolume/Lun2NS -vserver VServerNS2LUN2NS
ONTAPCluster::*> vsenv
Error: "vsenv" is not a recognized command
ONTAPCluster::*> vserver nvme namespace show -volume NS2LUN2NSVolume
There are no entries matching your query.
ONTAPCluster::*> vserver nvme namespace convert-from-lun -lun-path /vol/NS2LUN2NSVolume/Lun2NS -vserver VServerNS2LUN2NS
ONTAPCluster::*> lun show -volume NS2LUN2NSVolume
There are no entries matching your query.
ONTAPCluster::*> vserver nvme namespace show -volume NS2LUN2NSVolume
Vserver Path State Size Subsystem NSID
------- -------------------------------- ------- ------- ---------- ---------
VServerNS2LUN2NS /vol/NS2LUN2NSVolume/Lun2NS online 40MB - - <<< LUN Converted to NS
ONTAPCluster::*>
=========== Converting Namespace to LUN ===========
C2_sti85-vsim-ucs210c_cluster::*> lun show -volume NS2LUN2NSVolume
There are no entries matching your query.
C2_sti85-vsim-ucs210c_cluster::*> vserver nvme namespace show -volume NS2LUN2NSVolume
Vserver Path State Size Subsystem NSID
------- -------------------------------- ------- ------- ---------- ---------
VServerNS2LUN2NS
/vol/NS2LUN2NSVolume/Lun2NS online 40MB - -
C2_sti85-vsim-ucs210c_cluster::*> lun convert-from-namespace -
-vserver -namespace-path
C2_sti85-vsim-ucs210c_cluster::*> lun convert-from-namespace -namespace-path
<path> Path of the NVMe namespace
C2_sti85-vsim-ucs210c_cluster::*> lun convert-from-namespace -namespace-path /vol/NS2LUN2NSVolume/Lun2NS -vserver VServerNS2LUN2NS
C2_sti85-vsim-ucs210c_cluster::*> vserver nvme namespace show -volume NS2LUN2NSVolume
There are no entries matching your query.
C2_sti85-vsim-ucs210c_cluster::*> lun show -volume NS2LUN2NSVolume
Vserver Path State Mapped Type Size
--------- ------------------------------- ------- -------- -------- --------
VServerNS2LUN2NS /vol/NS2LUN2NSVolume/Lun2NS online unmapped linux 40MB <<< NS Converted to LUN
C2_sti85-vsim-ucs210c_cluster::*>
------------------------------------------------------------------------------------------------------------------------
7. Post Conversion , Map the LUN or NS to the respective iGroup or Subsystem appropriately.
8. Proceed with the Discovery of the LUN/Namespace at the Host.
9. File System Check at the Host and then can proceed with restarting IO on the LUN or NS.
