I suggest you should never directly be touching the /dev/dm* devices via that name. Always touch the actual named device (/dev/mpath, /dev/vgname/lv A given dm device can be a number of other devices (lv,s, mpath, mpath components, encrypted device, md raid, and probably some others). >From just the dm* name you really don't know which kind of device it is, and there is a lot of risk of confusion and/or data loss. I have debugged situations were someone went in and partitioned all of their /dev/dm* devices and some of those devices were actually the LV's and others were they created PV's on other LV's. Without a few commands you cannot easily know what the dm* device is, so access it via the more sensibly named device. On Wed, Mar 28, 2018 at 3:27 AM, Zdenek Kabelac <zkabelac@redhat.com> wrote: > Dne 27.3.2018 v 12:38 Michael Fladischer napsal(a): >> >> Hi, >> >> I'm unable to create PVs on Multipath-Volumes that are available at >> /dev/dm-NN where N~[0-9] but I can create them on single digit devices >> like /dev/dm-9: >> >> # pvcreate /dev/dm-6 >> Physical volume "/dev/dm-6" successfully created. >> >> # pvcreate /dev/dm-16 >> Device /dev/dm-16 not found (or ignored by filtering). >> >> My Version of LVM is 2.02.168 from Debian 9. >> The filter ist set to a permissive value: >> filter = [ "a|.*|" ] >> global_filter = [ "a|.*|" ] >> >> Any ideas why two or more digits in the device path can cause it to be >> filtered by pvcreate? >> > > > > Hi > > > lvm2 is detecting multipath 'component' devices - those are not allowed to > be used for pvcreate. > > You can use 'pvcreate -vvv' to get more information - there will be printed > the reason why devices are rejected.... > > Eventually if you can't figure this out yourself - provide this trace in > attachment. > > > Regards > > Zdenek > > > _______________________________________________ > 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/ _______________________________________________ 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/
