Sparse Image Files and Disk Space

If the host’s physical disk reaches a state where it has no available space, a virtual machine using a virtual disk based on a sparse image file is unable to write to its disk. Consequently, it reports I/O errors.

The Reiser file system, perceiving a corrupt disk environment, automatically sets the file system to read-only. If this situation happens, you should free up available space on the physical disk, remount the virtual machine’s file system, and set the file system back to read-write.

To check the actual disk requirements of a sparse image file, use the command du -h <image file>.