Sparsebundle on network share handling, TM

[Mac2013orlater]

Is it true for given network share (smb) Time Machine accepts single sparsebundle only? And multiple sparsbundle on one network share are not supported?

Local service of my nas reports these results from their test. If on starting TM backup from scratch on a network share some TM sparcebundle already placed there will be removed by TM.

QNAP nas stations support TM via AFP since years ago. Now I like to migrate my backups to TM on SMB but behaviour as described above is being observed which makes migration impossible. Any Mac id stored in raw sparsebundle allowing tm to identify if it ownes that or not?

Can community confirm if above is T.M. native and known behaviour?
Is this maybe a matter of just doing tumutil inheritbackup... additionally to handling performed already?

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Tiny Update
It is the content within sparsebundle not the container itself which is being wiped by TM as possibly not as own recognized. Container changes its name to purge or so for short rime.

 

[Mac2013orlater]

If T.M. via AFP on QNAP side some system service maintains user, location on storage volume of spursebundle image. I guess volume subdirectory .timemachine or so is then used. If T.M. via SMB much more control is in user hands, anyhow Qnap admin needs to determine the storage volume and create network share. For simplicity in the case here same volume is used and shared folder on volume of own choice. I believe by proceeding this way .timemachine and user's directory for SMB-T.M. are located at volume's some tree level.
No tests was done by myself due to lack of free resources. But local QNAP customer support reports to me the content of spursebundle was purged by T.M. after T.M. was run on this sparsebundle. Preceeding that sparsebundle was copied/moved from AFP-T.M. location to SMB-T.M. location.

Actually the question is if theoretically from T.M. point of view it should be possible to migrate from afp to smb whereby when on smb migrated sparsebundle can be still used to produce new backup increments?
Actually situation is more simple as in case here the need is for T.M. to have read access to backup and periodic backup verification or/and sparsebundle fsck is possible only as soon as on SMB, means new backup increments are not planned cause this migration is made along with upgrade to MacOS Sierra, for Sierra backup is going to be started from scratch.

 

[Mac2013orlater]

Yes, it is possible to switch T.M. backup on network share (sparsebundle-based) from AFP to SMB. Sparsebundle image needs to handled accordantly for this. Knowledge regarding data management/placement on side of machine addressed network share is provisioned by needs to be considered. More details follow as soon as some free resources.