apport information ** Tags added: apport-collected xenial
** Description changed: ---------- Configuration # echo -e $(grep VERSION= /etc/os-release)\\nSIGNATURE=\"$(cat /proc/version_signature)\" VERSION="16.04.3 LTS (Xenial Xerus)" SIGNATURE="Ubuntu 4.10.0-35.39~16.04.1-generic 4.10.17" # dpkg --list | grep zfs ii libzfs2linux 0.6.5.6-0ubuntu18 ii zfs-doc 0.6.5.6-0ubuntu18 ii zfs-initramfs 0.6.5.6-0ubuntu18 ii zfs-zed 0.6.5.6-0ubuntu18 ii zfsutils-linux 0.6.5.6-0ubuntu18 ---------- Fault: Creating an overlay of multiple directories on a ZFS volume does not work # df /var/tmp Filesystem Type 1K-blocks Used Available Use% Mounted on tank07/var/tmp zfs 129916288 128 129916160 1% /var/tmp # mkdir /var/tmp/{lower,middle,upper,workdir,overlay} # mount -t overlay overlay -olowerdir=/var/tmp/middle:/var/tmp/lower,upperdir=/var/tmp/upper,workdir=/var/tmp/workdir /var/tmp/overlay mount: wrong fs type, bad option, bad superblock on overlay, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg | tail or so. # dmesg|tail -1 [276328.438284] overlayfs: filesystem on '/var/tmp/upper' not supported as upperdir ---------- Control test 1: Creating an overlay of multiple directories on another filesystem works # df /tmp Filesystem Type 1K-blocks Used Available Use% Mounted on tmpfs tmpfs 1048576 133492 915084 13% /tmp # mkdir /tmp/{lower,middle,upper,workdir,overlay} # mount -t overlay overlay -olowerdir=/tmp/middle:/tmp/lower,upperdir=/tmp/upper,workdir=/tmp/workdir /tmp/overlay # mount | grep overlay overlay on /tmp/overlay type overlay (rw,relatime,lowerdir=/tmp/middle:/tmp/lower,upperdir=/tmp/upper,workdir=/tmp/workdir) ---------- Control test 2: Creating an overlay using AuFS works on ZFS volume and elsewhere # mount -t aufs -obr=/tmp/lower:/tmp/middle:/tmp/upper:/tmp/workdir none /tmp/overlay # mount -t aufs -obr=/var/tmp/lower:/var/tmp/middle:/var/tmp/upper:/var/tmp/workdir none /var/tmp/overlay # mount | grep aufs none on /var/tmp/overlay type aufs (rw,relatime,si=9ead1ecae778b250) none on /tmp/overlay type aufs (rw,relatime,si=9ead1ec9257d1250) ---------- Remark While the use of AuFS can be used as a workaround in the above scenario, AuFS in turn will not work with [fuse.]glusterfs mounts (this has been documented elsewhere). Given that OverlayFS is part of the (upstream) kernel and Ubuntu now officially supports ZFS, the above should be fixed. + --- + AlsaDevices: + total 0 + crw-rw---- 1 root audio 116, 1 Sep 18 16:12 seq + crw-rw---- 1 root audio 116, 33 Sep 18 16:12 timer + AplayDevices: Error: [Errno 2] No such file or directory + ApportVersion: 2.20.1-0ubuntu2.10 + Architecture: amd64 + ArecordDevices: Error: [Errno 2] No such file or directory + AudioDevicesInUse: Error: command ['fuser', '-v', '/dev/snd/seq', '/dev/snd/timer'] failed with exit code 1: + DistroRelease: Ubuntu 16.04 + IwConfig: Error: [Errno 2] No such file or directory + Lspci: Error: [Errno 2] No such file or directory + Lsusb: Error: [Errno 2] No such file or directory + MachineType: Red Hat KVM + NonfreeKernelModules: zfs zunicode zavl zcommon znvpair + Package: linux (not installed) + PciMultimedia: + + ProcFB: 0 cirrusdrmfb + ProcKernelCmdLine: BOOT_IMAGE=/ROOT/ubuntu1604@/boot/vmlinuz-4.10.0-35-generic root=ZFS=tank07/ROOT/ubuntu1604 ro + ProcVersionSignature: Ubuntu 4.10.0-35.39~16.04.1-generic 4.10.17 + RelatedPackageVersions: + linux-restricted-modules-4.10.0-35-generic N/A + linux-backports-modules-4.10.0-35-generic N/A + linux-firmware 1.157.12 + RfKill: Error: [Errno 2] No such file or directory + Tags: xenial + Uname: Linux 4.10.0-35-generic x86_64 + UpgradeStatus: No upgrade log present (probably fresh install) + UserGroups: + + _MarkForUpload: True + dmi.bios.date: 04/01/2014 + dmi.bios.vendor: SeaBIOS + dmi.bios.version: 1.9.1-5.el7_3.3 + dmi.chassis.type: 1 + dmi.chassis.vendor: Red Hat + dmi.chassis.version: RHEL 7.3.0 PC (i440FX + PIIX, 1996) + dmi.modalias: dmi:bvnSeaBIOS:bvr1.9.1-5.el7_3.3:bd04/01/2014:svnRedHat:pnKVM:pvrRHEL7.3.0PC(i440FX+PIIX,1996):cvnRedHat:ct1:cvrRHEL7.3.0PC(i440FX+PIIX,1996): + dmi.product.name: KVM + dmi.product.version: RHEL 7.3.0 PC (i440FX + PIIX, 1996) + dmi.sys.vendor: Red Hat ** Attachment added: "CRDA.txt" https://bugs.launchpad.net/bugs/1718761/+attachment/4954633/+files/CRDA.txt -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1718761 Title: It's not possible to use OverlayFS (mount -t overlay) to stack directories on a ZFS volume To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1718761/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs