Re: [Libguestfs] Question about mounting QCOW2 files....

[Adding libguestfs mailing list] On Sun, Oct 14, 2018 at 11:53:17AM -0400, Raghuram Devarakonda wrote: > Hi, > > In our project, we deal with quite large sparse files whose total size > runs into several hundred terabytes or even more, though actual > allocated size on disk is much smaller. The problem is that such large > files present issues for copying around, compression, or even for > computing checksums. I am wondering of I can use guestfs-tools to > mount a QCOW2 image and then use the image as sparse file. The idea is > that actual file on the disk would be compact though to our code, > sparse file interface is preserved. It's not very clear to me exactly what you want, but in general yes qcow2 is a good way to handle very large, sparse disk images. If you can be clearer about exactly what you mean by "mount" then I could answer the question better. For example, do you mean "mount a filesystem in the qcow2 image"? In which case use guestmount. If you mean "attach the qcow2 disk as a local device" then qemu-nbd can do this.