Hi @Henke,
I am assuming you are storing files on Azure files (SMB share) and using a file system agent to protect the share(s). I’m not sure if we’ve validated this but a quick google shows that it does support the attributes needed to allow archiving with stubbing (assuming you are using SMB and not Linux style share - which could work too but I’m not a Linux expert to know).
Since we don't have access to the server hosting the files, we can’t install the driver. This means that any client accessing the file share will need the driver installed in order to trigger a recall, assuming you want seamless access.
When a file is stubbed, the offline attribute is set - our file system agent knows how to handle these so that they don't trigger a recall. I know with OnePass archiving the sub is stored automatically as part of the OnePass job, further file system jobs won't need to backup the stub. If you are using non-onepass archiving I think the file may be backed up as a stub - which is beneficial should the stub become damaged, as you can restore the stubs easily.