The following is a list of guidelines for using the mIVolume utility:
D mIVolume does not allow you to initialize a volume currently in use.
D If you are initializing a disk for the first time, you must enter the bad spots listed in the manufacturer's report that accompanies each disk.
For more information on how to enter bad spots, refer to Entering Bad Spots.
D Once you initialize a volume, you use the BAD SPOT REPORT command to create a record of bad spots. You should save this record; you must have it if the volume
becomes corrupted. .
You can use the information the BAD SPOT REPORT command generates to create a file whose name you can enter in a [Bad spot] field of the MIVOLUME command form.. You then need not enter each bad spot
individually. Refer to Entering Bad Spots ..
o If you try to initialize a corrupted disk (that is, a disk the system cannot mount), you must enter all known bad spots.
o If you are initializing a volume for the first time or a volume that is corrupted, you must specify a device type in the MIVOLUME command form.
3·14 Initializing and Verifying XE520 Disks D If you are reinitializing a valid volume, you do not have
to specify the device type.
D If you interrupt the initialization operation, the volume becomes invalid and you must reinitialize the disk as a new disk.
D If you are reinitializing a valid BTOS volume, you can suppress the medium formatting operation by
specifying yes in the [Suppress format of medium?]
field. This reduces the time required to initialize the disk.
D The value specified for the maximum number of directories is rounded up to the nearest multiple of 15 to produce the size of the file [sys] <sys> Mfd.sys. Since you can expand this file only by reinitializing the disk, it is important to determine an appropriate value.
D mIVolume allocates File Header Block (FHB) sectors for each file. The value specified for the maximum number of files is multiplied by 1.5 to allow for a certain number of extension FHBs. This product is then rounded up to an even multiple of three times the number of sectors on each cylinder of the disk.
mIVolume locates these FHBs on the disk to ensure that the primary and secondary FHBs are located on
different cylinders, at different rotational positions, and (for system volumes) on different disk surfaces.
Since you can increase this number only by
reinitializing the disk, it is important to determine an appropriate value.
D The value specified for the maximum number of files in the <sys> directory is rounded up to the nearest multiple of 14. Because system performance is degraded if the volume is a system volume and this directory is more than 80% full, you must allow for more files than you needed.
Since you can expand this number only by reinitializing the disk, it is important to determine an appropriate value.
Bad Spots
If you are initializing a disk for the first time or are initializing a corrupted disk (that is, a disk no longer mountable by the system), you must enter a listing of known bad spots in the [Bad spots] field of the MIVOLUME command form.
Once you initialize a disk, the system maintains a coded list of the bad sectors in the file <sys> badblk.sys~
A sector is identified as defective (and therefore omitted from the Allocation Bit Map) for three reasons:
o You specified a bad spot in the sector in the MIVOLUME command form.
o Before initialization, the disk contained a valid BTOS volume and the sector was previously identified in the bad sector file as defective.
o The sector failed the surface tests of the mIVolume utility.
Identifying Bad Spots
You identify bad spots by their location on the disk. A disk location is designated by cylinder/head/sector or
cylinder/head/byte (a cylinder is sometimes referred to as a track).
Bad spot locations are designated by the format:
c/h/#s or c/h/b/l c is the cylinder number h is the head number s is the sector number b is the byte .number
1 is the length of the defect. You should always use the value 1 to specify the length of the defect.
All numbers used in identifying bad spots are in decimal.
The mIVolume utility converts all bad spot designations in the byte format to the sector format. When specifying bad spots in the MIVOLUME command form, you should use the sector format rather than the byte format.
3·16 Initializing and Verifying XE520 Disks Listing Current Bad Spots
To get a listing of bad spots, you specify a log file or print file name in the MIVOLUME or BAD SPOT REPORT
command form when you use one of these utilities. (Refer to Executing the BAD SPOT REPORT Command.)
--The report these utilities generate includes a listing of the bad spots currently stored in the <sys> BadBlk.sys file.
You can use this listing to create a file whose name you can enter in the [Bad spot] field instead of entering each bad spot individually. For more information, refer to Entering Bad Spots.
Entering Bad Spots
To enter bad spots in the MIVOLUME command form, you can enter each bad spot individually or enter the name of a file that contains a list of the bad spots.
To enter bad spots individually, you type each bad spot designation in one of the form's three [Bad spots) fields.
Do not break an individual bad spot entry over two fields.
If all the entries do not fit in the three fields, you must use the BTOS Editor to create a file that lists the bad spots, separating the bad spot designations by a space or carriage return. Then, in one [Bad spots] field, enter
@BadSpotFile, where BadSpotFile is the file you have listed the bad spots in.
If you saved the print file generated when you executed the MIVOLUME or BAD SPOT REPORT command on the volume, you can edit this file.
To create a bad spot file, use the following procedure:
1 Copy the print file to the file you enter in a [Bad spot]
field.
2 Use the BTOS Editor to delete all nonpertinent information from the print file.
The only information to keep in this file is the bad spot listing itself.
3 In the [Bad spot] field, enter @BadSpotFile, where BadSpotFile is the name of the file you edited.
Note: If you are executing mlVolume through a
eLi
runstatement and are listing bad spots individually, you must enclose the list of bad spot entries in parentheses.
Note About Bad Spots
Built-in disk drives are formatted for 591 bytes per sector (512 of which are for data), 16 sectors (0-15), 7 heads (0-6), and 645 cylinders (0-644). You cannot enter a defect on a cylinder greater than 644 or having a byte value greater than 9455. Also, you do not enter bad spots for cylinder 644, head 6; it is the last track on the disk and