Arch Linux

gwpl

Member

From: Warsaw, Poland

Registered: 2010-07-10

Posts: 28

LVM2 mirror segment monitoring function failed

Hello,

I've made a few mirrored LVM2 volumes (non-root - root is standard partition).

When running system I see :
(trying to not misstype, but take into account I am retyping from photo )

:: Activating LVM2 groups
  File-based locking installation failed
Child exited with code 5
  Unable to start dmeventd.
Child exited with code 5
  Unable to start dmeventd.
  vg0-Archive: event registration failed: No such process
  vg0/Archive: mirror segment monitoring function failed
(... repeats for all mirrored partitions...)

This is my mkinitcpio.conf

# cat /etc/mkinitcpio.conf  | grep -v '^#'
MODULES="dm_mod reiserfs"

BINARIES=""

FILES=""

HOOKS="base udev autodetect pata scsi sata mdadm lvm2 encrypt filesystems"

My rc,conf , MODULES and DAEMONS looks like:

MODULES=(slhc lp parport parport_pc dm-mod fuse vboxdrv)
DAEMONS=(syslog-ng network netfs iptables dbus hal crond dhcpd @openntpd)

My kernel is
# uname -srvmi
Linux 2.6.34-ARCH #1 SMP PREEMPT Sat Jun 19 00:07:49 CEST 2010 x86_64 AuthenticAMD
(currently don't want to upgrade, case some problems for my gpu reported after update, so waiting for solutions for gfx before upgrade)

Could you advice me:
How to check if my LV mirroring is working correctly and data are "safe" for one disk failure ?
How to fix those warnings on startup ?

Last edited by gwpl (2010-07-12 13:22:25)

hatten

Arch Linux f@h Team Member

From: Sweden, Borlange

Registered: 2009-02-23

Posts: 736

Re: LVM2 mirror segment monitoring function failed

If stability isn't a very important issue (ie, you got your data regularly backed up, as everybody should) try btrfs. Getting an lvm-like setup is a breeze.

gwpl

Member

From: Warsaw, Poland

Registered: 2010-07-10

Posts: 28

Re: LVM2 mirror segment monitoring function failed

If stability isn't a very important issue (ie, you got your data regularly backed up, as everybody should) try btrfs. Getting an lvm-like setup is a breeze.

Thanks for fast reply with advice. I've considered btrfs, but decided to wait a little bit before switching to btrfs.
So, btrfs sure, but in future.
(Btw. nice to read people recommending it, I hope stable future of this promising fs is soon).

Last edited by gwpl (2010-07-10 13:16:40)

gwpl

Member

From: Warsaw, Poland

Registered: 2010-07-10

Posts: 28

Re: LVM2 mirror segment monitoring function failed

Ok,

I am mailing with Alasadir G Kergon from redhat about advices, how to fix issue. It might involve patching rc.sysinit, and maybe adding something into rc.d . Could you give me some advice, whom should I mail for advice about preparing patch, whom to send this patch etc. ?

P.S. Don't worry, I have scripting and programming skills . Just need guidance community related, and archlinux architecture philosophy (also someone skilled with dmeventd etc stuff, cause I am just starting with lvm2 stuff).

thetrivialstuff

Member

Registered: 2006-05-10

Posts: 191

Re: LVM2 mirror segment monitoring function failed

I would have a look inside /etc/rc.sysinit and see what the "Activating LVM2 groups" section is trying to do -- then try running those same commands manually (in single-user mode if need be) with some verbose switches on. Hopefully something will say exactly what the problem is. Specifically, try starting dmeventd yourself and see if you can get it running, then add whatever it took to do that into the spot where rc.sysinit is trying to start it.

gwpl

Member

From: Warsaw, Poland

Registered: 2010-07-10

Posts: 28

Re: LVM2 mirror segment monitoring function failed

I've been nicely guided by Alasdair G Kergon to not start deventd till later and check out how Fedora does it. Advised to add "--sysinit" option on initial activation. Later - after "pivotroot and when filesystems sre all up" - then use "-- monitor y".

I suppose rc.sysinit should be patched to init lvm2 with "--sysinit", and later somewhere ,after running filesystems, dmeventd, etc to setup option "--monitor y".

btw. In what package is dmeventd and how to setup it ? (Searching arch wiki for dmeventd returned nothing).

Grzegorz Wierzowiecki

refs:
https://www.redhat.com/archives/linux-l … 00035.html
https://www.redhat.com/archives/linux-l … 00036.html
https://www.redhat.com/archives/linux-l … 00037.html
https://www.redhat.com/archives/linux-l … 00038.html

Last edited by gwpl (2010-07-12 13:19:28)