Linux block device simulation & Fuse

Question

Hello everyone

My project involves simulating a block device by remote host.

For testing I am using FUSE, my file system is a simple change of the "hello" example app, where instead of returning a constant string I just read data directly from a file.

When I try to mount the file normally (mount -o loop=/dev/loop1 ) it works well. When I load fuse and expose this file via it, all the normal file operations work. But mounting fails with "Permission denied".

Anyone has an idea where the "permission denied" is coming from ?

Any other methods to that will allow me to create a virtual device (only support block access) in users space, that will be mountable ?

Thanks in advance

Answer 1

The mount command is a real hell to use when it starts to print errors. Try "-v" but more often than not, the additional output won't help :(

Answer 2

Presumably the problem is that the FUSE filesystem doesn't support the features required to have loop-mounts on it.

Have you considered using a network block device instead, such as NBD or iSCSI target?

Answer 3

Are you executing with Root permission. You can trace the program with "strace" and then check where exactly this fails.