hpux 11.31/ia64: is vgchange a soft link?

[Doug O'Leary]

Hi,

I suspect my client's done something very silly; however, I don't have any other HPUX systems to compare it against.  Can anyone tell me, on a vanilla OS install, is vgchange a soft link?

# gsh all ls -ld /usr/sbin/vgchange
prdap1: lrwxr-xr-x 1 root sys 10 Jun 7 2007 /usr/sbin/vgchange -> ./lvchange
prdap2: lrwxr-xr-x 1 root sys 10 Jun 12 2007 /usr/sbin/vgchange -> ./lvchange
prdap3: lrwxr-xr-x 1 root sys 10 Nov 20 2007 /usr/sbin/vgchange -> ./lvchange
prddb1: lrwxr-xr-x 1 root sys 10 May 18 2007 /usr/sbin/vgchange -> ./lvchange
prddb2: lrwx------ 1 root sys 13 Dec 4 2011 /usr/sbin/vgchange -> ./lvm_wrapper
sapdev: lrwxr-xr-x 1 root sys 13 Jun 2 2009 /usr/sbin/vgchange -> ./lvm_wrapper
sapq07: lrwxr-xr-x 1 root sys 13 May 26 2009 /usr/sbin/vgchange -> ./lvm_wrapper
sapbck: lrwxr-xr-x 1 root sys 10 Aug 1 2011 /usr/sbin/vgchange -> ./lvchange

Some of these things don't look like the others and I'm not sure *any* of them are supposed to look like that!

Thanks for any info confirming/refuting this.

Doug

[Doug O'Leary]

Hey

It looks like they're supposed to be soft links.  

How I got onto this is I'm attempting a MCSG package failover.  The vgs wouldn't activate on the adoptive node.  The error was:

# vgchange -a e vgsapPRD
vgchange: Unable to execute the command: /usr/sbin/lvmcmd. Errno: 2.
# ls -ld /usr/sbin/lvmcmd
/usr/sbin/lvmcmd not found

A long listing of vgchange shows it a softlink and a scan of all of the client's HPs show all the vgchange commands as listed above.  Hence my question.  

The lvmcmd that lvm_wrapper is apparently looking for only exists on two recently patched systems.  On all other HPUX systems, all lvm commands are soft linked to lvchange.  Curiously, on the two recently patched boxes, lvchange is also linked to lvm_wrapper...

Not sure how the client's system got into this state; but, it's fixed now...

I believe I know how/why these links are there; however, if anyone has a link to some hard documentation on it, I'd appreciate seeing it.

Thanks.

Doug O'Leary

[Dennis Handly]

>if anyone has a link to some hard documentation on it

You could always try swverify to check the file's properties.

[Patrick Wallek]

On a couple of 11.31 servers:

11.31 root /root # ls -l /usr/sbin/vgchange
lrwxrwxrwx   1 root       sys             13 Jul 19 15:34 /usr/sbin/vgchange -> ./lvm_wrapper
11.31 root /root # uname -a
HP-UX abcd B.11.31 U 9000/800 atl5 unlimited-user license

11.31 root /root # ls -l /usr/sbin/vgchange
lrwxrwxrwx   1 root       sys             13 Jul 13 12:07 /usr/sbin/vgchange -> ./lvm_wrapper
11.31 root /root # uname -a
HP-UX abce B.11.31 U ia64 2815418294 unlimited-user license

It looks like 11.31 uses the lvm_wrapper script.

On prior version it looks like vgchange is its own executable.

[Bill Hassell]

This is a recent change for the lvm commands.

All versions of 11.23, 11.11, 11.00 and 10.20 have a single executable for all LVM commands and they are all hard linked together, 24 links for 10.20 up to 33 links for 11.23. I imagine that the design is to have one big program with 30+ different names. That way, a change such as LVM layout 2.x requires changes to one program. The program invokes the appropriate code depending the name used to start the program.

It would seem that the lvm_wrapper is doing te same thing.

[Dennis Handly]

>they are all hard linked together

One advantage of softlinks vs hardlinks is that when patching, you only have to deliver one file, not 1 file and N-1 hardlinks.