Disk Image Modes

Bochs can handle independent disk image format for each disk present on the ata interfaces. The disk image type is selected in the configuration file by the "mode" option of the ataX-xxx directives. If unspecified, the default "mode" is flat. Example:

ata0-master: type=disk, mode=flat, path=10M.sample, cylinders=306, heads=4, spt=17

Table 3. Supported Disk Modes

NameDescriptionFeatures
flat one file, flat layout  
concat multiple files, concatenated  
dll accessed through a DLL (developer specific, windows only)  
sparse stackable, commitable disks  
vmware3 vmware3 disk support  
undoable flat file with a commitable redolog  
growing one growing file  
volatile flat file with a volatile redolog  
z-undoable gziped flat file with a commitable redolog  
z-volatile gziped flat file with a volatile redolog  

Note

z-undoable and z-volatile modes are only available if the "--enable-compressed-hd" parameter was set at compile time.

Note

Please note for z-undoable and z-volatile modes, that, since reads are emulated by zlib, disk accesses are _VERY_ slow.

flat

concat

temporary text from old enable-split-hd option

      When enabled, this allows a series of partial hard disk image files to be
      treated as if it was one large file.  The .bochsrc specifies the first
      partial HD image (example win95-1) and then bochs searches for the other
      partial images in as a sequence (win95-2, win95-3, etc.) and opens them
      all.  Then, it treats the series as if there was a single large file
      created by "cat win95-1 win95-2 win95-3".  This trick works for both
      diskc and diskd.  All files must be a multiple of 512 bytes.

external

dll

sparse

vmware3

undoable

growing

volatile

z-undoable

z-volatile