From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [10.34.130.169] (dhcp130-169.brq.redhat.com [10.34.130.169]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u5OB03F5029137 for ; Fri, 24 Jun 2016 07:00:04 -0400 References: <5768578E.2010608@windriver.com> <576865BC.4020400@windriver.com> <57687182.8030309@windriver.com> <57687891.1090001@windriver.com> <4094fb9b-01d7-8358-8a91-fa65719af0e4@redhat.com> <57695BC4.3040205@windriver.com> <8771709a-3ab2-e485-ce87-5a6c51e8a9a9@redhat.com> <576AA614.6050800@windriver.com> <576C0FEF.7060301@windriver.com> <6629d697-bba0-aef0-f29f-60c4a35d00b2@redhat.com> <576C2447.9050403@windriver.com> From: Zdenek Kabelac Message-ID: Date: Fri, 24 Jun 2016 13:00:03 +0200 MIME-Version: 1.0 In-Reply-To: <576C2447.9050403@windriver.com> Content-Transfer-Encoding: 7bit Subject: Re: [linux-lvm] what creates the symlinks in /dev/ ? Reply-To: LVM general discussion and development List-Id: LVM general discussion and development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , List-Id: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: LVM general discussion and development Dne 23.6.2016 v 20:02 Chris Friesen napsal(a): > On 06/23/2016 11:21 AM, Zdenek Kabelac wrote: >> Dne 23.6.2016 v 18:35 Chris Friesen napsal(a): > >>> [root@centos7 centos]# vgscan --mknodes >>> Configuration setting "snapshot_autoextend_percent" invalid. It's not part >>> of any section. >>> Configuration setting "snapshot_autoextend_threshold" invalid. It's not part >>> of any section. >> >> fix your lvm.conf (uncomment sections) >> >>> Reading all physical volumes. This may take a while... >>> Found volume group "chris-volumes" using metadata type lvm2 >>> Found volume group "centos" using metadata type lvm2 >>> Found volume group "cinder-volumes" using metadata type lvm2 >>> The link /dev/chris-volumes/chris-volumes-pool should have been created by >> >> Ok - there seems to be internal bug in lvm2 - which incorrectly hints >> link creation for this case. >> >> There should not have been /dev/vg/pool link - this is correctly marked >> for udev - but incorrectly for udev validation. >> >> However the bug is actually not so much important - it just links >> to 'wrapper' device - and eventually we will resolve the problem even without >> this extra device in table. > > The problem that it causes for me is that when I run "vgchange -an > chris-volumes" it leaves the /dev/chris-volumes with a broken symlink in it > because udev doesn't remove the symlink added by vgscan. Yep - as said - in normal circumstance use should NOT run 'vgmknodes' as the created links will not be known/visible to udev - so this behavior is correct. > This causes the LVM OCF script in the "resource-agents" package to break, > because it is using the existance of the /dev/vg directory as a proxy for > whether the volume group is active (or really as you said earlier, whether > there are active volumes within the volume group). > > I reported this as a bug to the "resource-agents" package developers, and they > said that they can't actually call lvm commands in their "status" routines > because there have been cases where clustered LVM hung when querying status, > causing the OCF script to hang and monitoring to fail. > > Ultimately I'll see if I can work around it by not calling "vgscan --mknodes". yes please, start with this one... vgmknodes are really supposed to be used on some unique urgent problem - not executed in script every hour... But yes - lvm2 will need to fix link creation of pool-in-use... > Originally it was added in to fix some problems, but that was a while back so > things may behave properly now. Regards Zdenek