Bug 477040

Summary:	Creation of mirrored logical volume with VG extent-size of 1K fails
Product:	Red Hat Enterprise Linux 5	Reporter:	Milan Broz <mbroz>
Component:	lvm2	Assignee:	Milan Broz <mbroz>
Status:	CLOSED ERRATA	QA Contact:	Cluster QE <mspqa-list>
Severity:	medium	Docs Contact:
Priority:	medium
Version:	5.2	CC:	agk, cmarthal, dwysocha, edamato, heinzm, jbrassow, mbroz, prockai, pvrabec
Target Milestone:	rc
Target Release:	---
Hardware:	i386
OS:	Linux
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:
Clones:	490004 (view as bug list)		Environment:
Last Closed:	2009-09-02 11:57:13 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:
Bug Blocks:	490004

Description Milan Broz 2008-12-18 20:15:11 UTC

+++ This bug was initially created as a clone of Bug #471565 +++

Usespace part, lvm2 need calculate properly sized log device

Description of problem:
Creation of a mirrored LV with disk log fails, if the VG extent-size is 1K (2K and bigger works as expected).


Version-Release number of selected component (if applicable):
$ lvm version
  LVM version:     2.02.32-RHEL5 (2008-03-04)
  Library version: 1.02.24 (2007-12-20)
  Driver version:  4.11.5 


How reproducible:
Create a volume group with extent size of 1K and a mirrored logical volume with a disk based mirror log.


Steps to Reproduce:
$ dd if=/dev/zero of=/test/image[1,2,3] bs=1024k count=128
$ losetup /dev/loop0 /test/image1
$ losetup /dev/loop1 /test/image2
$ losetup /dev/loop2 /test/image3
$ pvcreate /dev/loop[0,1,2]
  Physical volume "/dev/loop[0,1,2]" successfully created
$ vgcreate -s 1K vg_mirror_test /dev/loop0 /dev/loop1 /dev/loop2
  Volume group "vg_mirror_test" successfully created
$ lvcreate -L 64M -m 1 -n lv_mirror1 vg_mirror_test /dev/loop0 /dev/loop1 /dev/loop2:0-0
  /dev/cdrom: open failed: Read-only file system
 
No more output shown.

  
Actual results:
dmesg and /var/log/messages shows this:
 
===
Nov  4 17:43:17 nagtest-web1 lvm[16895]: Log device, 253:2, has failed.  
Nov  4 17:43:17 nagtest-web1 lvm[16895]: Device failure in vg_mirror_test-lv_mirror1
Nov  4 17:43:17 nagtest-web1 lvm[16895]: WARNING: dev_open(/etc/lvm/lvm.conf) called while suspended
Nov  4 17:43:16 nagtest-web1 kernel: attempt to access beyond end of device
Nov  4 17:43:22 nagtest-web1 kernel: dm-2: rw=16, want=3, limit=2
Nov  4 17:43:22 nagtest-web1 kernel: device-mapper: mirror log: Failed to read header on mirror log device, 253:2
Nov  4 17:43:22 nagtest-web1 kernel: attempt to access beyond end of device
Nov  4 17:43:22 nagtest-web1 kernel: dm-2: rw=17, want=3, limit=2
Nov  4 17:43:22 nagtest-web1 kernel: device-mapper: mirror log: Failed to write header on mirror log device, 253:2
Nov  4 17:43:22 nagtest-web1 kernel: device-mapper: raid1: log resume failed
Nov  4 17:43:22 nagtest-web1 kernel: attempt to access beyond end of device
Nov  4 17:43:22 nagtest-web1 kernel: dm-2: rw=17, want=3, limit=2
Nov  4 17:43:22 nagtest-web1 kernel: attempt to access beyond end of device
Nov  4 17:43:22 nagtest-web1 kernel: dm-2: rw=17, want=3, limit=2
Nov  4 17:43:22 nagtest-web1 kernel: attempt to access beyond end of device
===
'top' lists the kmirrord process with high cpu utilization:
PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
5541 root      20  -5     0    0    0 R 95.9  0.0  12:30.75 kmirrord
===
 
The errors continue forever ...
It seems that a 1K mirror log (because the size of the mirror log is equal to the size of the VG phsical extend) isn't big enough to hold the log information!


Expected results:
$ lvcreate -L 64M -m 1 -n lv_mirror1 vg_mirror_test /dev/loop0 /dev/loop1 /dev/loop2:0-0
  /dev/cdrom: open failed: Read-only file system
  Logical volume "lv_mirror1" created

Comment 1 Milan Broz 2008-12-19 15:31:03 UTC

Fixed in upstream cvs in lvm2 2.02.44, planned for inclusion in RHEL5.4.

Comment 2 Milan Broz 2009-05-21 09:22:15 UTC

Fix in version lvm2-2.02.46-1.el5.

Comment 4 Corey Marthaler 2009-05-26 20:14:48 UTC

Fix verified in lvm2-2.02.46-2.el5.

[root@grant-03 ~]# vgcreate -s 1K grant /dev/sdb1 /dev/sdb2 /dev/sdb3 
  Volume group "grant" successfully created

[root@grant-03 ~]# lvcreate -L 64M -m 1 -n mirror grant 
  Logical volume "mirror" created

[root@grant-03 ~]# lvs -a -o +devices
  LV                VG         Attr   LSize  Origin Snap%  Move Log         Copy%  Convert Devices                              
  LogVol00          VolGroup00 -wi-ao 64.56G                                               /dev/sda2(0)                         
  LogVol01          VolGroup00 -wi-ao  9.81G                                               /dev/sda2(2066)                      
  mirror            grant      mwi-a- 64.00M                    mirror_mlog 100.00         mirror_mimage_0(0),mirror_mimage_1(0)
  [mirror_mimage_0] grant      iwi-ao 64.00M                                               /dev/sdb2(0)                         
  [mirror_mimage_1] grant      iwi-ao 64.00M                                               /dev/sdb3(0)                         
  [mirror_mlog]     grant      lwi-ao  2.00K                                               /dev/sdb1(0)

Comment 5 Corey Marthaler 2009-05-26 20:37:43 UTC

Just a note, this was verified w/o specifying the disks on the lvcreate cmdline. When specifying the disks and allowing 0 space for the log on a 1K extent VG, you'll end up hitting bug 502671.

Comment 7 errata-xmlrpc 2009-09-02 11:57:13 UTC

An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on therefore solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHBA-2009-1393.html