Re: [gentoo-user] what is lvmetad?

[covici@ccs.covici.com]

Alan McKinnon <alan.mckinnon@gmail.com> wrote:

> On 28/02/2014 21:47, covici@ccs.covici.com wrote:
> > Alan McKinnon <alan.mckinnon@gmail.com> wrote:
> > 
> >> On 28/02/2014 21:12, covici@ccs.covici.com wrote:
> >>> In the newest  lvm, there is something called lvmetad, but it won't
> >>> start because /run/lvm is missing.  When I created by hand, it then
> >>> started, but when I then started lvm which would not start without
> >>> lvmetad, it said lvmetad was started, but disabled.
> >>>
> >>> Can anyone tell me what is  going on here?
> >>>
> >>> Thanks.
> >>>
> >>
> >> the ebuild issues an elog:
> >>
> >>  * Make sure the "lvm" init script is in the runlevels:
> >>  * # rc-update add lvm boot
> >>  *
> >>  * Make sure to enable lvmetad in /etc/lvm/lvm.conf if you want
> >>  * to enable lvm autoactivation and metadata caching.
> >>
> >>
> >> Did you notice it and follow it?
> > 
> > I did not ignore, but I could not find where use_lvmetad was and up till
> > now it never made any difference, but I see where it is.  but lvmetad
> > would not start at all till I manually created /run/lvm.
> > 
> > 
> 
> 
> /run is a tmpfs, so something must mkdir it as startup time. I reckon
> that is device-mapper:
> 
> $ grep /run/lvm *
> device-mapper:  checkpath -q -d -m 0700 -o root:root /run/lvm /run/lock/lvm
> lvmetad:pidfile="/var/run/lvmetad.pid"
> 
> 
> Do you have device-mapper configured to run?
> I must admit I see oddities sometimes on my lvm-enabled hosts where the
> /var/run -> /run symlinks are missing.
> I think you should file a bug, either the code is wrong or the
> docs/elogs are insufficient here

Maybe I will do that as the lvmetad is  started before devicemapper if I
remember correctly or somehow the dependencies are wrong.  I am not sure
why its a requirement, I don't scan new lvm volumes very often at all,
so its not saving any time, if that is why it exists.

-- 
Your life is like a penny.  You're going to lose it.  The question is:
How do
you spend it?

         John Covici
         covici@ccs.covici.com