A volume server for flexibly combining mirroring, striping and concatenation in virtual storage devices includes virtualization functionality and a layout table. The virtualization functionality may be configured to aggregate storage within one or more block devices into a logical volume. The layout table may include multiple extent entries, where each extent entry represents a mapping of an extent of block device storage to a virtual address range of the logical volume, including an indication of a stripe of the logical volume to which the extent is mapped. An overlap in virtual address range between a first and a second extent entry may indicate mirroring of the overlapping blocks at each extent. In response to a storage request, the virtualization functionality may obtain a block device address corresponding to the logical volume virtual address of the storage request from the layout table.