Volume Mirroring

[Qcheck]

Good morning All,

When I tried to check the server whether every file system has been mounted or not with the following command, it doesn't show anything? Any ideas????

# lvdisplay /dev/vg00/lvol* | grep mirror

Thanks

[Pete Randall · Accepted solution]

Try

# lvdisplay /dev/vg00/lvol* | grep -i mirror


Pete

[Qcheck]

Never mind everyone, I should have used "grep -i mirror", it worked....Monday morning I was so paniced when I couldn't see any mirrors. Because cat /etc/lvmtab, doesn't show anything except one line. Is that normal???

[Qcheck]

Hi Pete,

Thank you....I got it....

[MarkSyder]

He knows you got it, but he still deserves points for giving you the right answer!

Mark Syder (like the drink but spelt different)

[TwoProc]

lvdisplay -v /dev/vg00/lvolxxxx
If you're mirrored, on each line you'll see:
A: the logical extent number
B: The first device of the mirror followed by the PE on that disk, followed its state (current/stale/etc).
C) The second device of the mirror followed by the PE on that disk, followed its state (current/stale/etc).

If you've got only four columns of data for each logical extent, your lv is not mirrored. If you've got 7 columns here your lv is mirrored.

[Patrick Wallek]

The /etc/lvmtab is a binary file, so cat will not show anything. To look at the lvmtab file you need to use the 'strings' command.

# strings /etc/lvmtab

You will still see some strange characters, but don't be alarmed.

The lvmtab file will not show what you want either though. There's no information about mirrors in the lvmtab file.

[Qcheck]

Hi John,

How and where can I check the columns to find if I have four or seven columns????

How abt /etc/lvmtab??I just want to know if my /etc/lvmtab is fine....

And Mark! You are right...and I am very generous in giving points.....so in that way, should be lucky to answer my questions...hahahaha...;)

Thank you all...

[Qcheck]

Thank you Pat...

U all got points now....

[TwoProc]

when you do the lvdisplay -v /dev/vgxx/lvolxxx

You'll see a list of the logical extents, its the very long display after the "introductory details".

A snippet of mirrored extents look like:

00241 /dev/dsk/c0t6d0 01816 current /dev/dsk/c10t6d0 00816 current
00242 /dev/dsk/c0t6d0 01817 current /dev/dsk/c10t6d0 00817 current
00243 /dev/dsk/c0t6d0 01818 current /dev/dsk/c10t6d0 00818 current
00244 /dev/dsk/c0t6d0 01819 current /dev/dsk/c10t6d0 00819 current
00245 /dev/dsk/c0t6d0 01820 current /dev/dsk/c10t6d0 00820 current
00246 /dev/dsk/c0t6d0 01821 current /dev/dsk/c10t6d0 00821 current
00247 /dev/dsk/c0t6d0 01822 current /dev/dsk/c10t6d0 00822 current
00248 /dev/dsk/c0t6d0 01823 current /dev/dsk/c10t6d0 00823 current
00249 /dev/dsk/c0t6d0 01824 current /dev/dsk/c10t6d0 00824 current

A snippet of unmirrored extents look like:

00241 /dev/dsk/c0t6d0 01816 current
00242 /dev/dsk/c0t6d0 01817 current
00243 /dev/dsk/c0t6d0 01818 current
00244 /dev/dsk/c0t6d0 01819 current
00245 /dev/dsk/c0t6d0 01820 current
00246 /dev/dsk/c0t6d0 01821 current
00247 /dev/dsk/c0t6d0 01822 current
00248 /dev/dsk/c0t6d0 01823 current
00249 /dev/dsk/c0t6d0 01824 current

[Jollyjet]

Hi,
to check all the file system is mounted you need to follow on bdf output

lvdisplay /dev/vg00/lvol* | grep mirror

the above one will tell you whether it is mirrored or not

[Qcheck]

Hi John and Jolly,

Thank you for the information and I really appreciate all your time. I am clear now and all my filesystems are mirrored.

Thanks again