corrupted vg00.conf file

[Jerome Salyers]

hi, we have a problem that our vg00.conf file under /etc/lvmconf is corrupted and so our /etc/lvmtab is also corrupt... i need to know how to recreate the vg00.conf file...

the problem is in my vg00.conf file, when i do a strings, i get multiple entrys of 1ia after my entries of LVMREC01, and all other entries...

i've checked other vg00.conf files on other machines, and this line with 1ia does not appear...

on our corrupt system, the 1ia line then appears in the lvmtab file...

we've tried using vgscan to recreate the lvmtab file, but the 1ia line still appears...

the system is a HPL200 running hpux11...

thanks for any help

jerome

[T G Manikandan · Accepted solution]

#vgcfgbackup -u /dev/vg00.

It updates the latest LVM configuration and creates files in /etc/lvmconf.

check for the man pages of
vgcfgbackup.

Thanks

[Stefan Farrelly]

Hmm. After removing lvmtab and running vgscan to recreate it when you then do a strings /etc/lvmtab it still comes back corrupt ?? can we see the output ?

If so it looks like the LVMREC on the header of the disk is possible corrupt. It doesnt look good - you may need to blask the disk and start again.

[Dietmar Konermann]

You cannot really check the consistency of that files using strings(1)! The files are binary and it is of course possible that other patterns "look like" C strings for the strings(1) command.

I appended a tool that dumps the lvmtab contents in a more reliable way...

Regards...
Dietmar.

[Stefan Farrelly]

Dietmar,

your attachment is no good - can you check/retry ?

Cheers,

Stefan

[Dietmar Konermann]

2nd trial..

[Dietmar Konermann]

Oh my dear... something's wrong here.

Ok, here is the source.

# cc -o dumplvmtab dumplvmtab.c


---
/* dumplvmtab, @(#)dumplvmtab.c (2000-01-17) dietmar_konermann@hp.com */
#include
#include
#include
#include
#include

main (argc, argv)
int argc;
char ** argv;
{
char header[12];
char vg_info[1054];
char pv_info[1028];

size_t fd;
int vg_cnt, pv_cnt, vgno, pvno;

if ((fd = open("/etc/lvmtab",O_RDONLY)) == -1)
{
perror ("Unable to read /etc/lvmtab");
exit (1);
}

if (read (fd, &header, sizeof (header)) != sizeof (header))
{
perror ("Unable to read lvmtab header");
exit (1);
}

vg_cnt=*(int*)(header+0x04);
printf ("vers_no:%04hX zero:%04hX vg_count:%08X\n",
*(short*)header,
*(short*)(header+0x02),
vg_cnt=*(int*)(header+0x04));

for (vgno=0; vgno {
if (read (fd, &vg_info, sizeof (vg_info)) != sizeof (vg_info))
{
perror ("Unable to read vg_info");
exit (1);
}

vg_info[1023]=0;
printf ("vg_path:%s\n vg_id:%08X%08X vg_state:%04X vg_incno:%08X pv_cnt:%08X\n",
vg_info,
*(int*) (vg_info+0x400),
*(int*) (vg_info+0x404),
*(short*) (vg_info+0x408),
*(short*) (vg_info+0x40c),
pv_cnt=*(short*) (vg_info+0x410));

for (pvno=0; pvno {
if (read (fd, &pv_info, sizeof (pv_info)) != sizeof (pv_info))
{
perror ("Unable to read pv_info");
exit (1);
}

pv_info[1023]=0;
printf (" pv_path:%s\n", pv_info);
}
}

close (fd);

}

[Jerome Salyers]

dieter, that one doesn't work either... i'm very interested in this tool...

thanks

jerome

[Hamdy Al-Sebaey]

Jerome,

Just have a look at the man pages of
vgcfgbackup.

regards,
Hamdy