1FORMAT(8V) FORMAT(8V)
2
6 format - how to format disk packs
7
9 There are two ways to format disk packs. The simplest is to use the
10 format program. The alternative is to use the DEC standard formatting
11 software which operates under the DEC diagnostic supervisor. This man‐
12 ual page describes the operation of format, then concludes with some
13 remarks about using the DEC formatter.
14 Format is a standalone program used to format and check disks prior to
16 constructing file systems. In addition to the formatting operation,
17 format records any bad sectors encountered according to DEC standard
18 144. Formatting is performed one track at a time by writing the appro‐
19 priate headers and a test pattern and then checking the sector by read‐
20 ing and verifying the pattern, using the controller's ECC for error
21 detection. A sector is marked bad if an unrecoverable media error is
22 detected, or if a correctable ECC error too many bits in length is
23 detected (such errors are indicated as ``ECC'' in the summary printed
24 upon completing the format operation). After the entire disk has been
25 formatted and checked, the total number of errors are reported, any bad
26 sectors and skip sectors are marked, and a bad sector forwarding table
27 is written to the disk in the first five even numbered sectors of the
28 last track. It is also possible to reformat sections of the disk in
29 units of tracks. Format may be used on any UNIBUS or MASSBUS drive
30 supported by the up and hp device drivers which uses 4-byte headers
31 (everything except RP's).
32 The test pattern used during the media check may be selected from one
34 of: 0xf00f (RH750 worst case), 0xec6d (media worst case), and 0xa5a5
35 (alternating 1's and 0's). Normally the media worst case pattern is
36 used.
37 Format also has an option to perform an extended “severe burn-in,”
39 which makes a number of passes using different patterns. The number of
40 passes can be selected at run time, up to a maximum of 48, with provi‐
41 sion for additional passes or termination after the preselected number
42 of passes. This test runs for many hours, depending on the disk and
43 processor.
44 Each time format is run to format an entire disk, a completely new bad
46 sector table is generated based on errors encountered while formatting.
47 The device driver, however, will always attempt to read any existing
48 bad sector table when the device is first opened. Thus, if a disk pack
49 has never previously been formatted, or has been formatted with differ‐
50 ent sectoring, five error messages will be printed when the driver
51 attempts to read the bad sector table; these diagnostics should be
52 ignored.
53 Formatting a 400 megabyte disk on a MASSBUS disk controller usually
55 takes about 20 minutes. Formatting on a UNIBUS disk controller takes
56 significantly longer. For every hundredth cylinder formatted format
57 prints a message indicating the current cylinder being formatted.
58 (This message is just to reassure people that nothing is is amiss.)
59 Format uses the standard notation of the standalone I/O library in
61 identifying a drive to be formatted. A drive is specified as zz(x,y),
62 where zz refers to the controller type (either hp or up), x is the unit
63 number of the drive; 8 times the UNIBUS or MASSBUS adaptor number plus
64 the MASSBUS drive number or UNIBUS drive unit number; and y is the file
65 system partition on drive x (this should always be 0). For example,
66 ``hp(1,0)'' indicates that drive 1 on MASSBUS adaptor 0 should be for‐
67 matted; while ``up(10,0)'' indicates that UNIBUS drive 2 on UNIBUS
68 adaptor 1 should be formatted.
69 Before each formatting attempt, format prompts the user in case debug‐
71 ging should be enabled in the appropriate device driver. A carriage
72 return disables debugging information.
73 Format should be used prior to building file systems (with newfs(8)) to
75 insure that all sectors with uncorrectable media errors are remapped.
76 If a drive develops uncorrectable defects after formatting, either
77 bad144(8) or badsect(8) should be able to avoid the bad sectors.
78
80 A sample run of format is shown below. In this example (using a
81 VAX-11/780), format is loaded from the console floppy; on an 11/750
82 format will be loaded from the root file system with boot(8) following
83 a “B/3” command. Boldface means user input. As usual, ``#'' and ``@''
84 may be used to edit input.
85 >>>L FORMAT
87 LOAD DONE, 00004400 BYTES LOADED
88 >>>S 2
89 Disk format/check utility
90 Enable debugging (0=none, 1=bse, 2=ecc, 3=bse+ecc)? 0
92 Device to format? hp(8,0)
93 (error messages may occur as old bad sector table is read)
94 Formatting drive hp0 on adaptor 1: verify (yes/no)? yes
95 Device data: #cylinders=842, #tracks=20, #sectors=48
96 Starting cylinder (0):
97 Starting track (0):
98 Ending cylinder (841):
99 Ending track (19):
100 Available test patterns are:
101 1 - (f00f) RH750 worst case
102 2 - (ec6d) media worst case
103 3 - (a5a5) alternating 1's and 0's
104 4 - (ffff) Severe burnin (up to 48 passes)
105 Pattern (one of the above, other to restart)? 2
106 Maximum number of bit errors to allow for soft ECC (3):
107 Start formatting...make sure the drive is online
108 ...
109 (soft ecc's and other errors are reported as they occur)
110 ...
111 (if 4 write check errors were found, the program terminates like this...)
112 ...
113 Errors:
114 Bad sector: 0
115 Write check: 4
116 Hard ECC: 0
117 Other hard: 0
118 Marked bad: 0
119 Skipped: 0
120 Total of 4 hard errors revectored.
121 Writing bad sector table at block 808272
122 (808272 is the block # of the first block in the bad sector table)
123 Done
124 (...program restarts to allow formatting other disks)
125 (...to abort halt machine with ^P)
126
129 The diagnostics are intended to be self explanatory.
130
132 Warning: These instructions are for people with 11/780 CPU's. The
133 steps needed for 11/750 or 11/730 cpu's are similar, but not covered in
134 detail here.
135 The formatting procedures are different for each type of disk. Listed
137 here are the formatting procedures for RK07's, RP0X, and RM0X disks.
138 You should shut down UNIX and halt the machine to do any disk format‐
140 ting. Make certain you put in the pack you want formatted. It is also
141 a good idea to spin down or write protect the disks you don't want to
142 format, just in case.
143 Formatting an RK07. Load the console floppy labeled, "RX11 VAX DSK LD
145 DEV #1" in the console disk drive, and type the following commands:
146 >>>BOOT
147 DIAGNOSTIC SUPERVISOR. ZZ-ESSAA-X5.0-119 23-JAN-1980 12:44:40.03
148 DS>ATTACH DW780 SBI DW0 3 5
149 DS>ATTACH RK611 DMA
150 DS>ATTACH RK07 DW0 DMA0
151 DS>SELECT DMA0
152 DS>LOAD EVRAC
153 DS>START/SEC:PACKINIT
154 Formatting an RP0X. Follow the above procedures except that the ATTACH
156 and SELECT lines should read:
157 DS>ATTACH RH780 SBI RH0 8 5
158 DS>ATTACH RP0X RH0 DBA0(RP0X is, e.g. RP06)
159 DS>SELECT DBA0
160 This is for drive 0 on mba0; use 9 instead of 8 for mba1, etc.
162 Formatting an RM0X. Follow the above procedures except that the ATTACH
164 and SELECT lines should read:
165 DS>ATTACH RH780 SBI RH0 8 5
166 DS>ATTACH RM0X RH0 DRA0
167 DS>SELECT DRA0
168 Don't forget to put your UNIX console floppy back in the floppy disk
170 drive.
171
173 bad144(8), badsect(8), newfs(8)
174
176 An equivalent facility should be available which operates under a run‐
177 ning UNIX system.
178 It should be possible to reformat or verify part or all of a disk, then
180 update the existing bad sector table.
1814th Berkeley Distribution May 22, 1986 FORMAT(8V)