lvmtab includes some unidentified characters (322 Views)
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Super Advisor
Posts: 303
Registered: ‎12-10-2004
Message 1 of 10 (322 Views)

lvmtab includes some unidentified characters

my /etc/lvmtab has some unidentified characters, I have a vg00 which has one disk in it. whatever i do i still have the output of lvmtab:
/dev/vg00
DF%s
/dev/dsk/c2t1d0s2

if i try to delicatelly remove these characters using vi, it will be fine but after a vgscan i get that the lvmtab file is wrong and should be replaced.
the system came out of the box this way, how to fix this?
Frequent Advisor
Posts: 47
Registered: ‎06-25-2006
Message 2 of 10 (322 Views)

Re: lvmtab includes some unidentified characters

lvmtab is not a text file. You can see it with strings:

sapap1:root> strings /etc/lvmtab
/dev/vg00
/dev/dsk/c0t6d0s2
/dev/dsk/c2t6d0s2
/dev/vg_EPC_D01
/dev/dsk/c13t0d1


Dont modify lvmtab!!!
Honored Contributor
Posts: 1,367
Registered: ‎05-14-1996
Message 3 of 10 (322 Views)

Re: lvmtab includes some unidentified characters

simon,

DO NOT edit /etc/lvmtab with vi. You will corrupt the file. lvmtab is a BINARY file. Those unidentifiable characters are binary data.

To edit lvmtab, use lv/pv/vg commands, such as lvcreate, lvreduce, etc.

The proper way to view the contents of lvmtab is:

# strings /etc/lvmtab

PCS
Super Advisor
Posts: 303
Registered: ‎12-10-2004
Message 4 of 10 (322 Views)

Re: lvmtab includes some unidentified characters

I was not clear enough, I am getting the unidentified characters from lvmtab using the strings command so:
strings /etc/lvmtab -->
/dev/vg00
DF%s
/dev/dsk/c2t1d0s2

what does the DF%s means, how to get rid of it.
Honored Contributor
Posts: 1,367
Registered: ‎05-14-1996
Message 5 of 10 (322 Views)

Re: lvmtab includes some unidentified characters

simon,

# man strings

The 'strings' command returns what it believes to be printable, or ASCII, strings in a file. The junk you see is just 'strings' giving you a false positive. It is just making an educated guess, after all.

You can exclude this unwanted output by increasing the minimum string length like this (just make sure you're not excluding lines you do want):

# strings -n 8 /etc/lvmtab

or with grep:

# strings /etc/lvmtab | grep -v 'DF%s'

PCS

Acclaimed Contributor
Posts: 21,184
Registered: ‎07-06-2000
Message 6 of 10 (322 Views)

Re: lvmtab includes some unidentified characters

Hi Simon:

As already stated, the '/etc/lvmtab' file is a binary file. The 'strings' command attempts to produce readable output by examining groups of four characters at a time.

In reality, the '/etc/lvmtab' contains not only the volume group names and their associated device files, but the LVM VGID (Volume Group ID) that uniquely identifies each volume group.

You file is *not* corrupt!

Regards!

...JRF...
Honored Contributor
Posts: 13,876
Registered: ‎06-21-2000
Message 7 of 10 (322 Views)

Re: lvmtab includes some unidentified characters

That is ABSOLUTELY NORMAL for the /etc/lvmtab file. You DO NOT have a problem. Quit trying to fix a problem that doesn't exist.

Honored Contributor
Posts: 7,167
Registered: ‎06-04-2001
Message 8 of 10 (322 Views)

Re: lvmtab includes some unidentified characters

Nothing wrong with that - unless you did a vi and saved it.

If so:

mv /etc/lvmtab /etc/lvmtab.bad
vgscan

Rgds...Geoff
Proverbs 3:5,6 Trust in the Lord with all your heart and lean not on your own understanding; in all your ways acknowledge him, and he will make all your paths straight.
Super Advisor
Posts: 303
Registered: ‎12-10-2004
Message 9 of 10 (322 Views)

Re: lvmtab includes some unidentified characters

Thx a lot,
Ok, i will not touch it.
However i would have liked it to be without those character :).
Acclaimed Contributor
Posts: 23,857
Registered: ‎10-02-2001
Message 10 of 10 (322 Views)

Re: lvmtab includes some unidentified characters

Consider to accept the strings output or try

strings -n 6 /etc/lvmtab

Hope this helps!
Regards
Torsten.

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