Mike, Thanks for helping me out with this. I was not aware of the lvm2-monitor service. I have configured it and now the snapshot lvs get removed once the merging is complete. I will investigate the dracut udev rules to see if I can fix the I/O errors (although for now I can work around by putting 'nodmraid' on my kernel command line). Thanks again and have a good day! Dusty Mabe On Wed, Feb 8, 2012 at 2:52 PM, Mike Snitzer <snitzer@redhat.com> wrote: > On Wed, Feb 08 2012 at 2:10pm -0500, > Dusty Mabe <dustymabe@gmail.com> wrote: > >> Hi, >> >> I am on CentOS 6.2 (kernel-2.6.32-220.el6.x86_64.rpm, >> lvm2-2.02.87-6.el6.x86_64.rpm). I am seeing an issue similar to >> https://bugzilla.redhat.com/show_bug.cgi?id=651007 where I still have >> snapshot lvs present after I merge them back into the origin devices. >> >> The steps are : >> >> - create snapshot >> - lvconvert --merge (on open lv so that the merge will happen on next reboot) >> - reboot >> - after reboot the lvs have been restored to original, but 'lvs -a' >> still shows snapshot lvs >> >> I was seeing many I/O errors during bootup like are shown in comment >> 13 of https://bugzilla.redhat.com/show_bug.cgi?id=651402 . I disabled >> dmraid on bootup and I no longer get these errors but the snapshot lvs >> are still present after the merge has taken place. > > Odd considering dracut's modules.d/90dmraid/61-dmraid-imsm.rules was > patched to be DM_UDEV_DISABLE_OTHER_RULES_FLAG aware in RHEL 6.1 (via RH > bug# 650959). > >> lvchange --refresh will clear up the snapshot lvs. > > Implies the lvm2 polldaemon code isn't cleaning up the merged snapshot > lvs after the merge completes: I'm not sure what is going on there > because the issue was fixed in RHEL 6.1 (via RH bug# 645488). > >> I do notice that dracut is touching the lvs (the ones to be merged) >> early in the boot process: >> >> dracut: Scanning devices vda2 for LVM logical volumes vgroot/plat_root >> dracut: inactive Original '/dev/vgroot/plat_root' [1.00 GiB] inherit >> dracut: inactive Original '/dev/vgroot/plat_var' [1.00 GiB] inherit >> dracut: inactive Original '/dev/vgroot/plat_usr' [4.00 GiB] inherit >> dracut: inactive '/dev/vgroot/plat_tmp' [1.00 GiB] inherit >> EXT4-fs (dm-2): orphan cleanup on readonly fs >> EXT4-fs (dm-2): 1 orphan inode deleted >> EXT4-fs (dm-2): recovery complete >> EXT4-fs (dm-2): mounted filesystem with ordered data mode. Opts: >> dracut: Mounted root filesystem /dev/mapper/vgroot-plat_root >> SELinux: Disabled at runtime. >> type=1404 audit(1328721625.889:2): selinux=0 auid=4294967295 ses=4294967295 >> dracut: >> dracut: Switching root >> Welcome to CentOS >> >> >> Is there an issue with dracut accessing and mounting the root lv >> (which was set to be merged on next activation) ? > > Activating the root LV will initiate the merge. The fact that you only > need to 'lvchange --refresh' to clean up the dangling snapshot lvs means > that the merge did complete. > > Once the system pivots ("dracut: Switching root") the normal lvm-monitor > service should initiate both monitoring and polling of all active lvs. > Do you have the lvm2-monitor service enabled? And do you see messages > like the following at startup?: > Background polling started for 1 logical volume(s) in volume group "vgroot" _______________________________________________ linux-lvm mailing list linux-lvm@redhat.com https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
