I would like to make my AS400 to save entire system (go save, option 21) in a network location instead of a physical tap device. I have not iscsi devices connected. I have already created a virtual tap (type 63B0) with a catalog file mounted, and I can save and restore from it. I have tried to save the catalog file in a savf file and then to move that savf via ftp in a network location. My question is: is it possible to make a go save --> 21 option indicating as device a savf instead of a tap?
Generally this question should go to Server Fault. That is the reason for the close votes. But, there are only a few questions there about IBM i and no one there on a regular basis answers these questions.
So... No, a save file can only contain a save of objects from a single library at a time. So you cannot do go save --> 21 to a save file.
But you do not need to put a virtual tape image in a save file to move it off the system. Think of a virtual tape image like an .iso image that you could burn to a CD. It isn't really an .iso image, but it is stored in the IFS as a single file. These images can be FTP'd as is to any other system and added to an image catalog on that system. Or they can be stored on a server somewhere as a backup and then transferred again to a new system to be used in a restore operation.
You can find documentation on how to move virtual tape images to a different system in the IBM Knowledge Center.