Specific disk information can be defined for emulated disks under Avanti.  This is particularly useful to support older versions of Tru64 UNIX.

vendor
Disk vendor name. An empty vendor defaults to DEC.

model_num
Disk model name.

rev_num
Disk firmware revision. When model_num is empty, Avanti selects its default vendor, model, and revision, replacing any separate vendor or rev_num value. Set vendor, model_num, and rev_num together when overriding the automatic identity.

write_share (default: false)
Allow another process on the same Windows host to open the image file for writing. This changes only the host file-sharing mode; it does not coordinate cluster members or protect an unclustered filesystem from corruption. Use it only for an exact, validated guest-cluster configuration.

Warning: Using the write_share feature to share disks with non-clustered Avanti instances is not recommended.  Doing so may result in disk corruption.

serial_num
Disk serial number, at most 255 bytes.  If left blank, Avanti will generate a unique serial number for each disk and CD device.

Note: OpenVMS, Tru64 UNIX V3.x, and Tru64 UNIX V4.x ignore serial number settings.  Tru64 UNIX V5.x requires unique serial numbers for all disk and CD devices.

autocreate_size (default: 0)
If the disk container file is missing when the emulator starts, a nonzero value tells Avanti to try to create it at this size, up to 2 TiB. Avanti stages the image and publishes it only after creation succeeds; an existing file that cannot be opened is not overwritten. The size must be a multiple of 512 bytes. Use K, M, G, or T for binary multiples of 1024; for example, 4G creates a 4-gibibyte image. Leave this at 0 for an existing image so an open failure is reported rather than treated as a request to create the file.

sparse (default: false)
When Avanti creates a new image, request a Windows sparse file. A sparse image initially consumes less host storage and grows as guest data is written, but later writes may take longer. This setting has no effect when opening an existing image; if the host file system rejects the sparse request, Avanti creates an ordinary allocated image instead.

tcq (default: false)
Advertise tagged command queuing (TCQ) support to the guest. TCQ also requires disconnect to be enabled. Historical OpenVMS cluster configurations used this option on quorum disks, but that requirement has not been revalidated for every supported guest release; follow the installed guest's documentation and validate the exact cluster.

Warning: Historical field reports state that TCQ interfered with some Tru64 UNIX installations. This has not been reproduced across the Avanti 5.1.0 guest matrix. Leave TCQ disabled during installation unless the exact guest release and storage configuration have been validated with it enabled.

disconnect (default: true)
Allow the disk to disconnect and later reselect during large SCSI I/O operations. This is normal SCSI behavior and lets other devices use the bus while this disk's operation is in progress. TCQ requires disconnect to remain enabled.

random_access (default: true)
Tell Windows that the image will be accessed randomly. Leave this enabled for normal disk and CD-ROM images.

round_up (default: false)
If a writable existing image is not a multiple of the 512-byte sector size, permanently append zero bytes up to the next 512-byte boundary before mounting it. Avanti aborts the mount if Windows cannot complete and verify the change. Leave this disabled for ordinary disk images. The new-image dialog rejects an incorrectly sized existing image, so this compatibility option is mainly for carefully reviewed hand-edited configurations. Back up the host file before enabling it.

heads, cylinders, sectors (default: 0)
Override the disk geometry reported to the guest. Heads and sectors may be 0 through 255; cylinders may be 0 through 65,535. Leave all three values at 0 to calculate a geometry automatically. An override is used only when heads × cylinders × sectors exactly equals the image size in 512-byte blocks; otherwise Avanti logs a warning and calculates the geometry.

read_delay (default: 0)
Request an additional delay after each successful image read, expressed in microseconds, up to 2,147,482,648. Zero adds no delay. Ordinary timing rounds a nonzero request up to a whole millisecond, so 1 through 1000 request 1 millisecond and 1001 through 2000 request 2 milliseconds.

write_delay (default: 0)
Request an additional delay after each successful image write, with the same range, microsecond input, and whole-millisecond rounding as read_delay.

write_through (default: true)
Enable write-through caching.  Changes are written directly to the raw disk or container file.  If write through is disabled, there is a risk of losing data if the host system goes down unexpectedly. A guest SYNCHRONIZE CACHE command waits for earlier writes to complete and for Windows to flush the backing handle; a host flush failure is reported to the guest.

debug (default: false)
Reserved for a purpose-built diagnostic version supplied by Migration Specialties. This setting has no effect in an ordinary Avanti build.