Is there any ndmpcopy support for flexgroups

[Tas]

I will need to migrate a lot of data from FlexVols to FlexGroups. Anyone know if there is a twinkle in NetApp’s eye about this?  I understand I can go from a flexvol to a flexgroup, but I need to do it at a branche within the flexvol’s tree. Actually, perhaps two to four thousand branches;  we need to restructure and re-organize data. 

[Ontapforrum]

Hi,

Starting with ONTAP 9.7, NDMP is supported on FlexGroup volumes:
The "ndmpcopy" command is supported for data transfer between FlexVol and FlexGroup volumes.

http://docs.netapp.com/ontap-9/index.jsp?topic=%2Fcom.netapp.doc.dot-cm-ptbrg%2FGUID-9A0D1602-8969-4FB5-81E9-332FFD1E2676.html&anchor=:~:text=The%20nd....

Thanks!

[Tas]

I read that in the manual.  However, it does not specify whether I can supply a flexvol sub-tree to copy, or if it only copies the flexvol to the flexgroup.  I need to restructure data as I am copying it, so I need to specify a particular directory tree, under which all files and directories will be moved.

The docs also do not specify if I can provide a destination sub-tree path to copy to, or if it will simply write it to the root of the flexgroup.

TasP

[Ontapforrum]

"ndmpcopy" is a file-level copy tool (it doesn't care about blocks), which means it deals at 'directory' level which is a file-system level. So, I am hoping that if you provide a directory/sub-tree it should be able to write to that.

I have not dealt with flex-group in practical terms, but based on the documentation around it, It seems flex -group volume is simply a collection of flexvols acting as a "single entity",  considering this theory,  when you copy a directory(files) to the directory in flex group it should ideally mimic a flex-vol and do all that redirection automatically internally but on the surface behave as if it is flexvol. If that is so, then it should ideally work, could you not try a test copy of a directory to the flex-group directory.

[TMACMD]

I have done some limited testing in a simulated environment.

Please refer to https://www.netapp.com/us/media/tr-4571.pdf

There is a link in this doc referring to KB

https://kb.netapp.com/Advice_and_Troubleshooting/Data_Storage_Software/ONTAP_OS/How_to_run_ndmpcopy_in_Clustered_Data_ONTAP

I setup an ONTAP 9.7 cluster. I created a FlexVol with 5000+ files (1K or less for testing) in many directories.

I was able to run this command:

system node run -node cluster1-01 -command ndmpcopy -sa ndmpuser:1tUMETJJN9sIyCJw -da ndmpuser:1tUMETJJN9sIyCJw 192.168.0.200:/nas/vol01 192.168.0.200:/nas/fg01

Which copied a flexvol to a flexgroup at the top level.

I also tried:

system node run -node cluster1-01 -command ndmpcopy -sa ndmpuser:1tUMETJJN9sIyCJw -da ndmpuser:1tUMETJJN9sIyCJw 192.168.0.200:/nas/vol01/d1/s1 192.168.0.200:/nas/fg01/D1/s1

which copied a couple of directories down (not even qtrees, regular directories).

Now, It did not 100% evenly distribute, but it still did a pretty good job.

/vol/fg01__0001/ 1200     408401      0%  /fg01                      nas

/vol/fg01__0002/ 1600     408001      0%  ---                        nas

/vol/fg01__0003/ 1603     407998      0%  ---                        nas

/vol/fg01__0004/ 1203     408398      0%  ---                        nas

/vol/vol01/ 5308     158522      3%  /vol01                     nas