On Tue, Nov 17, 2020 at 04:00:10PM +0800, heming.zhao@xxxxxxxx wrote: > Hello LVM-maintainers, > > Currently activation/auto_activation_volume_list is not enable and it does the default behavior: > pvscan will activate all the devices on booting. > > This rule will trigger a clumsy process in HA (corosync+pacemaker stack) env. > > ## let me show the scenario: > > 2 nodes (A & B) share a disk, and using systemid to manage vg/lv on this shared disk. > (keep the activation/auto_activation_volume_list default style: comment out this cfg item) > > (below steps come from resource-agent LVM-active script) > 1. Node A own & active shared vg/lv, node B standby status. > 2. A reboot, B detect & wait for A rejoined cluster. > 3. because systemid doesn't be changed, lvm2-pvscan@.service will active the vg/lv on A during booting. > 4. A finishes reboot, B starts to switch systemid & active shared vg/lv. > 5. on B, pacemaker detects lvm resource is running on both nodes. > 6. on B, pacemaker restarts lvm resource and enable it on single node. > > ## rootcause: > > we can see step 3,4,5 is useless if step 3 is non-existent. > So the rootcause is step <3>: node A auto activate shared vg/lv. I believe there's an assumption that the system or a user will not activate LVs that are managed by the cluster, i.e. only LVM-activate will activate LVs managed by the cluster. Perhaps we could make some attempt to enforce that, or at least make sure the instructions for LVM-activate make it clear what to do. > ## discussion (how to fix): > > Could activation/auto_activation_volume_list support a new symbol/function like "!". > e.g. > auto_activation_volume_list = [ "!vg1", "!vg2/lvol1" ] > the '!' means lvm absolutely doesn't active this vg1 & vg2/lvol1 automatically. > > my question: > Does it acceptable for LVM2 adding this new function? auto_activation_volume_list is difficult to use IMO, and I don't think many people use it. Your suggestion sounds reasonable, but I've wondered if autoactivation should be a property set on the VG or LV itself (i.e. in the metadata)? The "activationskip" flag is a possible way to handle the unwanted autoactivation, and also seems to justify the idea of making autoactivation a similar flag. Dave _______________________________________________ linux-lvm mailing list linux-lvm@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
