Description of problem: When using large numbers of physical volumes it is recommended to create some with --metadatacopies=0 to improve tool performance. The vgdisplay command will show how many metadata copies exist in the volume group, but not which PVs they reside on. Currently this can only be determined by running pvdisplay for each PV in the VG. For a metadata-containing PV the output will be like: # pvdisplay /dev/loop0 --- Physical volume --- PV Name /dev/loop0 VG Name t0 PV Size 64.00 MB / not usable 4.00 MB Allocatable yes PE Size (KByte) 4096 Total PE 15 Free PE 15 Allocated PE 0 PV UUID 3CD0to-e2vD-adwE-1GS4-Icyl-3lPd-WdcE4U Whereas a non-metadata containing PV that is a member of a VG will look like an unused PV: # pvdisplay /dev/loop1 --- NEW Physical volume --- PV Name /dev/loop1 VG Name PV Size 64.00 MB Allocatable NO PE Size (KByte) 0 Total PE 0 Free PE 0 Allocated PE 0 PV UUID drpyTg-wsM9-LODi-enmN-c02m-UiG8-ZfmQim Version-Release number of selected component (if applicable): lvm2-2.02.21-5.el4, lvm2-2.02.24-1.fc7, lvm2 CVS 20070707. How reproducible: 100% Steps to Reproduce: 1. Create a volume group with #MDAS < #PVs: pvcreate --metadatacopies=1 /dev/loop0 pvcreate --metadatacopies=0 /dev/loop1 vgcreate t0 /dev/loop0 /dev/loop1 2. Try to determine which PV contains the MDA with LVM2 tools Actual results: LVM2 tools cannot directly reveal this information Expected results: LVM2 tools can directly reveal this information Additional info:
Upstream commit adding support for vg_mda_count and pv_mda_count to reporting tools: http://sourceware.org/cgi-bin/cvsweb.cgi/LVM2/WHATS_NEW.diff?cvsroot=lvm2&r1=1.648&r2=1.649
This request was evaluated by Red Hat Product Management for inclusion in a Red Hat Enterprise Linux maintenance release. Product Management has requested further review of this request by Red Hat Engineering, for potential inclusion in a Red Hat Enterprise Linux Update release for currently deployed products. This request is not yet committed for inclusion in an Update release.
*** Bug 202886 has been marked as a duplicate of this bug. ***
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 the 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-2007-0753.html