** Description changed: + ==== Begin SRU Template ==== + [Impact] + Overlayfs allows a user to mount the root filesystem read-only + and put an overlay over it. + It handles mounting of the root filesystem in the initramfs, and updates + /etc/fstab to account for non-root filesystems and generally make + /etc/fstab "correct". + + systemd can get confused by a /etc/fstab that looks like this: + + LABEL=cloudimg-rootfs /media/root-ro/ ext4 ro,defaults,noauto 0 0 + /media/root-ro/ / overlay lowerdir=... + + It would not recognize that the LABEL=cloudimg-rootfs image *was* mounted. + This would lead to boot ordering cycles. The fix that was ultimately + applied was just to comment out the line for /media/root-ro. + + That way systemd wouldnt try to ensure that /media/root-ro got mounted. + + [Test Case] + TBD + + [Regression Potential] + Not to omany things would depend on the /etc/fstab that exists in + an system booted with overlayroot. Something that was reading /etc/fstab + could be confused by this change. + + [Other Info] + This change is believed to fix bug 1680197 as well, but due to the + sporadic nature, we are not certain. + + ==== End SRU Template ==== + In the open-iscsi test we boot a read-only root iscsi target, using overlayroot. Transiently this operation fails, ultimately leading to emergency shell. Since this occurs in automated test, there is no access to that console (it is being logged to a file). The open iscsi test that triggers this is described at [1], including how to run it. Most recently, the open-iscsi version 2.0.873+git0.3b4b4500-14ubuntu17 has run both successfully and failed when running for trigger cloud-utils and systemd [2] I am attaching a tarball with logs and artifacts from the autopackage test runs here for posterity. In the failure case we see evidence of failure at [ 52.729092] systemd[1]: media-root\x2dro.mount: Found ordering cycle on media-root\x2dro.mount/start [ 52.730938] systemd[1]: media-root\x2dro.mount: Found dependency on -.mount/start [ 52.735138] systemd[1]: media-root\x2dro.mount: Found dependency on media-root\x2dro.mount/start [ 52.739910] systemd[1]: Unable to break cycle [ 52.744992] systemd[1]: Requested transaction contains an unfixable cyclic ordering dependency: Resource deadlock avoided And then it all goes sour later with: [ TIME ] Timed out waiting for device dev-disk-by\x2dlabel-UEFI.device. [DEPEND] Dependency failed for /boot/efi. [DEPEND] Dependency failed for Local File Systems. [ TIME ] Timed out waiting for device VIRTUAL-DISK cloudimg-rootfs. for reference, the image's fstab is: LABEL=cloudimg-rootfs / ext4 defaults 0 0 LABEL=UEFI /boot/efi vfat defaults 0 0 but /etc/fstab is updated by overlayroot in the initramfs, and as such contains the following: # # This fstab is in an overlay. The real one can be found at # /media/root-ro/etc/fstab # The original entry for '/' and other mounts have been updated to be placed # under /media/root-ro. # To permanently modify this (or any other file), you should change-root into # a writable view of the underlying filesystem using: # sudo overlayroot-chroot # LABEL=cloudimg-rootfs /media/root-ro/ ext4 ro,defaults 0 0 /media/root-ro/ / overlay lowerdir=/media/root-ro/,upperdir=/media/root-rw/overlay/,workdir=/media/root-rw/overlay-workdir/_ 0 0 LABEL=UEFI /boot/efi vfat defaults 0 0 # overlayroot:fs-unsupported -- [1] https://git.launchpad.net/~usd-import-team/ubuntu/+source/open-iscsi/tree/debian/tests/README-boot-test.md?h=ubuntu/devel [2] http://autopkgtest.ubuntu.com/packages/o/open-iscsi/zesty/amd64 ProblemType: Bug DistroRelease: Ubuntu 17.04 Package: open-iscsi 2.0.873+git0.3b4b4500-14ubuntu17 ProcVersionSignature: User Name 4.9.0-15.16-generic 4.9.5 Uname: Linux 4.9.0-15-generic x86_64 ApportVersion: 2.20.4-0ubuntu2 Architecture: amd64 Date: Tue Feb 21 15:50:58 2017 ProcEnviron: TERM=xterm-256color PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=en_US.UTF-8 SHELL=/bin/bash SourcePackage: open-iscsi UpgradeStatus: No upgrade log present (probably fresh install) modified.conffile..etc.iscsi.iscsid.conf: [inaccessible: [Errno 13] Permission denied: '/etc/iscsi/iscsid.conf'] Related bugs: * bug 1680197: Zesty deployments failing sporadically * bug 1723183: transient systemd ordering issue when using overlayroot - * bug 1732028: [systemd] transient boot fail with overlayroot + * bug 1732028: [systemd] transient boot fail with overlayroot
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1666573 Title: transient systemd ordering cycle in boot with overlayroot ver read- only open-iscsi root To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/cloud-initramfs-tools/+bug/1666573/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
