[ovirt-devel] GFS2 mount via symlink problem

Hi, this issues i described on Red Hat bugzilla entry #888711 [1], but I'll recap here since there is come confusion (mostly my fault, sorry!) in the bug. System setup: CentOS 6.5 fully up to date SGI IS5000 SAS storage with 2 servers connected oVirt is 3.4.0 The Storage configured in oVirt is PosixFS, vfs type is gfs2 gfs2 is on top of CLVM Red Hat Cluster Manager (cman) is used to manage CLVM The issue is summarized by: [root@fionn-virt1 ~]# grep virtstorage /etc/fstab /dev/mapper/vg_is5000-lv_virtstorage /gfs2/virtstorage gfs2 noatime,nodiratime,nobarrier 0 0 [root@fionn-virt1 ~]# grep virtstorage /proc/mounts /dev/dm-13 /gfs2/virtstorage gfs2 rw,seclabel,noatime,nodiratime,hostdata=jid=0,nobarrier 0 0 /dev/dm-13 /rhev/data-center/mnt/_dev_mapper_vg__is5000-lv__virtstorage gfs2 rw,seclabel,noatime,nodiratime,hostdata=jid=0,nobarrier 0 0 [root@fionn-virt1 ~]# grep virtstorage /etc/mtab /dev/mapper/vg_is5000-lv_virtstorage /gfs2/virtstorage gfs2 rw,seclabel,noatime,nodiratime,hostdata=jid=0,nobarrier 0 0 /dev/mapper/vg_is5000-lv_virtstorage /rhev/data-center/mnt/_dev_mapper_vg__is5000-lv__virtstorage gfs2 rw,seclabel,noatime,nodiratime,hostdata=jid=0,nobarrier 0 0 The storage is mounted twice, first by the gfs2 init script and then by ovirt. As you can see even if both ovirt and gfs2 init script used the /dev/mapper/name symlink, in proc mounts there is the real device specified, the one the symlink is pointing to. I have no clue why only GFS2 does that (at least ext* FS are not, didn't checked anything else TBO, I have only ext* FS on other LVM volumes on the same system). In this case oVirt fails to check if the FS is mounted, since there is no entry in /proc/mounts matching the device name specified (the /dev/mapper/name one). I my example above I already applied a fix for that, so it is actually working. I've submitted a fix to ovirt gerrit, see [2], [3] and [4] (the latter is a unit test for checking gfs2). Note that [2] alone is not correct, it needs [3] as well to not break some other setup. Dan Kenigsberg of Red Hat suggested to move the discussion here, since this is a weird issue (why just GFS2 resolves the symlink?). I'm looking for advise, comments to the fix I proposed, but also about if this is actually the better fix? Like fixing GFS2 in the first place. That said I still think this should be handled by ovirt. It doesn't really matter if in /proc/mounts you have the symlink or the real device, it is the same mount Kind regards Enrico [1] https://bugzilla.redhat.com/show_bug.cgi?id=888711 [2] http://gerrit.ovirt.org/27321 [3] http://gerrit.ovirt.org/27425 [4] http://gerrit.ovirt.org/27514