topic Re: bad blocks in Operating System - HP-UX

bad blocks

David Watts — Fri, 03 Jan 2003 11:40:47 GMT

Anyone know how to mark a block on a disk as being bad ?

I used to do this many, many years ago when an fsck finds a block it couldn't read.

I have a file system that fails the fsck with :
vxfs fsck: fsck read failure bno = 1715, off = 0, len = 1024

Re: bad blocks

Eugeny Brychkov — Fri, 03 Jan 2003 12:00:52 GMT

David,
modern SCSI disk can relocate bad blocks by themselves. OS is also capable to do it, but not root volume - it should be contiguous.
What's disk model? Please post 'diskinfo -v' here.
Try dd'ing raw disk (rdsk) to /dev/null to check if there's really surface defect or fsck has corrupt tables referencing inexistent track
Eugeny

Re: bad blocks

Jose Mosquera — Fri, 03 Jan 2003 12:09:57 GMT

Hi,

Take a look:
http://forums.itrc.hp.com/cm/QuestionAnswer/1,,0x62e7d211e18ad5118ff10090279cd0f9,00.html

Rgds.

Re: bad blocks

Shahul — Fri, 03 Jan 2003 12:44:34 GMT

Hi

If you have not disabled the bad block reallocation in LVM, You don't need to worry about this. While creating lvol you can use -r switch for enabling/disabling the bad block reallocation. eg

#lvcreate -r n/y -L size vgname

If you have not given -r switch, LVM will take that as y. For more information see man page of lvcreate. You can even do this with lvchange command.

Hope this will help you.

Best of luck
Shahul

Re: bad blocks

David Watts — Fri, 03 Jan 2003 13:19:47 GMT

dd comes back with an I/O read error too !

here's the diskinfo:

#diskinfo -v /dev/rdsk/c0t5d0
SCSI describe of /dev/rdsk/c0t5d0:
vendor: SEAGATE
product id: ST34573WC
type: direct access
size: 4194157 Kbytes
bytes per sector: 512
rev level: HP05
blocks per disk: 8388314
ISO version: 0
ECMA version: 0
ANSI version: 2
removable media: no
response format: 2
(Additional inquiry bytes: (32)4e (33)35 (34)39 (35)36 (36)38 (37)35 (38)38 (39)0 (40)0 (41)0 (42)0 (43)0 (44)0 (45)0 (46)0 (47)0 (48)0 (49)0 (50)0 (51)0 (52)0 (53)0 (54)0 (55)0 (56)0 (57)0 (58)0 (59)0 (60)0 (61)0 (62)0 (63)0 (64)0 (65)0 (66)0 (67)0 (68)0 (69)0 (70)0 (71)0 (72)0 (73)0 (74)0 (75)0 (76)0 (77)0 (78)0 (79)0 (80)0 (81)0 (82)0 (83)0 (84)0 (85)0 (86)0 (87)0 (88)0 (89)0 (90)0 (91)0 (92)43 (93)6f (94)70 (95)79 (96)72 (97)69 (98)67 (99)68 (100)74 (101)20 (102)28 (103)63 (104)29 (105)20 (106)31 (107)39 (108)39 (109)37 (110)20 (111)53 (112)65 (113)61 (114)67 (115)61 (116)74 (117)65 (118)20 (119)41 (120)6c (121)6c (122)20 (123)0 (124)7f (125)fe (126)da (127)0 (128)0 (129)2 (130)0 (131)0 (132)0 (133)0 (134)0 (135)0 (136)0 (137)0 (138)0 )

Re: bad blocks

Eugeny Brychkov — Fri, 03 Jan 2003 14:07:39 GMT

Bad disk as soon as dd shows error. I suspect c0t5d0 is in vg00 and has LVM bad block relocation turned off. So the best solution for you is to do backup (using tar or ignite) and replace the disk
Eugeny