topic Re: lvmtab corrupted in Operating System - HP-UX

lvmtab corrupted

sassou — Sun, 09 Jan 2005 05:53:30 GMT

Dear,
The output of the command strings /etc/lvmtab
/dev/vg00
MAb#-
/dev/dsk/c2t0d0
/dev/dsk/c2t1d0
I don't understand what is MAb#,
On this node I just imported vg and create and remove it
I need your help
KSF

Re: lvmtab corrupted

Robert-Jan Goossens — Sun, 09 Jan 2005 06:07:01 GMT

Hu Kuzo,

The /etc/lvmtab file is binary. Because the strings(1) command
is looking for ASCII strings in a binary file, ocassionaly
strange characters will appear.

/dev/vg00
MAb#-
/dev/dsk/c2t0d0
/dev/dsk/c2t1d0

You have nothing to worry about when you see this display.
strings on /etc/lvmtab is not a command that is supposed to
tell you about the vg configurations on your system. You are
supposed to use vgdisplay on the individual vg's.

The strings command is just a way to "cheat" and see info on all
the vg's at once. It leverages how strings pulls ascii characters
out of unformated files and so if any strings of ascii characters
exist other than the vg info then they will be displayed.

Regards,
Robert-Jan

Re: lvmtab corrupted

Stf — Sun, 09 Jan 2005 06:52:39 GMT

Hello,

if you want to correct it and to have a "look good" lvmtab you can save /etc/lvmtab in other directory and recreate it:

# mv /etc/lvmtab /tmp/lvmtab.old
# vgscan -v -a

Stf ;-)

Re: lvmtab corrupted

Bill Hassell — Sun, 09 Jan 2005 20:07:16 GMT

Recreating lvmtab will likely produce the same result. As mentioned, lvmtab is NOT an ASCII file and contains a bunch of binary numbers and character strings. Using the strings command is a hack to see the device files (which are ASCII strings). But some of the binary numbers may look like ASCII strings but are meaningless. The numbers are only meaningful to the LVM code.

Re: lvmtab corrupted

Trond Haugen — Mon, 10 Jan 2005 03:10:08 GMT

As already explained /etc/lvmtab ins't a ASCII file and doing strings is a hack. When doing it I always use 'strings /etc/lvmtab | grep dev'.

Regards,
Trond

Re: lvmtab corrupted

Nguyen Anh Tien — Sun, 16 Jan 2005 04:50:17 GMT

Do not worry. It is OK. lvmtab alway contains unfamily character. (binary format).
But i recommend you "export -p -m" all vgs (expecially vg00) to back it up. when problem occur vgimport again.
tienna