Bug 1071264
| Summary: | Report a clueful error when attempting to revert to an external disk snapshot (offline) | ||||||
|---|---|---|---|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Kashyap Chamarthy <kchamart> | ||||
| Component: | libvirt | Assignee: | Peter Krempa <pkrempa> | ||||
| Status: | CLOSED NEXTRELEASE | QA Contact: | Fedora Extras Quality Assurance <extras-qa> | ||||
| Severity: | unspecified | Docs Contact: | |||||
| Priority: | unspecified | ||||||
| Version: | rawhide | CC: | berrange, clalancette, itamar, jforbes, jyang, laine, libvirt-maint, pkrempa, veillard, virt-maint | ||||
| Target Milestone: | --- | ||||||
| Target Release: | --- | ||||||
| Hardware: | Unspecified | ||||||
| OS: | Unspecified | ||||||
| Whiteboard: | |||||||
| Fixed In Version: | Doc Type: | Bug Fix | |||||
| Doc Text: | Story Points: | --- | |||||
| Clone Of: | Environment: | ||||||
| Last Closed: | 2014-03-04 10:16:37 UTC | Type: | Bug | ||||
| Regression: | --- | Mount Type: | --- | ||||
| Documentation: | --- | CRM: | |||||
| Verified Versions: | Category: | --- | |||||
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |||||
| Cloudforms Team: | --- | Target Upstream Version: | |||||
| Embargoed: | |||||||
| Bug Depends On: | |||||||
| Bug Blocks: | 1124854 | ||||||
| Attachments: |
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Created attachment 869011 [details]
stderr of 'virsh snapshot-revert' with LIBVIRT_DEBUG=1
Hmmm, the disk only snapshot of an offline domain is apparently not created properly. Fixed upstream:
commit d410e6f19d944ad78bc9257726d613597db00701
Author: Peter Krempa <pkrempa>
Date: Tue Mar 4 10:06:22 2014 +0100
qemu: snapshot: Use better check when reverting external snapshots
https://bugzilla.redhat.com/show_bug.cgi?id=1071264
Reverting of external snapshots is not supported currently. The check
that is present doesn't properly check for all aspects that make a
snapshot external. Use virDomainSnapshotIsExternal() to do the check.
As the bug is filed against rawhide, closing as nextrelease.
Thanks for the fix, just re-tested with latest git commit:
Build libvirt from git
----------------------
$ yum-builddep libvirt -y
$ git clone git://libvirt.org/libvirt.git && cd libvirt
$ git log | head -1
commit ea1eadd6a31f2cce3f62f17619eac04d59b68fde
$ ./autogen.sh
$ make -j4
$ make check
$ make rpm
$ yum update *.rpm
Test
----
$ sudo virsh domblklist ostack-controller
Target Source
------------------------------------------------
vda /var/lib/libvirt/images/ostack-controller.qcow2
$ sudo virsh snapshot-create-as ostack-controller \
snap2 "snap-9MAR2014" --disk-only
Domain snapshot snap2 created
$ sudo virsh domblklist ostack-controller
Target Source
------------------------------------------------
vda /var/lib/libvirt/images/ostack-controller.snap2
$ sudo virsh snapshot-list ostack-controller
Name Creation Time State
------------------------------------------------------------
snap2 2014-03-10 16:51:06 +0530 shutoff
snap1-working-controller 2013-12-12 19:58:05 +0530 shutoff
$ sudo virsh snapshot-revert ostack-controller snap2
error: unsupported configuration: revert to external snapshot not supported yet
|
Description of problem ---------------------- Attempting to revert to an external (offline) disk snapshot throws: error: An error occurred, but the cause is unknown which is not very useful nor does it hint any action the user need to take. Relevant error (for complete stderr, refer the attachment) from LIBVIRT_DEBUG=1 (when attepmted to revert to an external disk snapshot): error: 2014-02-28 17:07:04.116+0000: 5951: debug : virEventPollCleanupTimeouts:553 : Found 0 out of 0 timeout slots used, releasing 0 An error occurred, but the cause is unknown Version ------- $ uname -r; rpm -q libvirt-daemon-kvm qemu 3.14.0-0.rc4.git0.1.fc21.x86_64 libvirt-daemon-kvm-1.2.1-2.fc21.x86_64 qemu-1.7.0-4.fc21.x86_64 How reproducible: Consistently. Steps to Reproduce ------------------ 1. Ensure the Domain is offline. 2. Create an external disk only snapshot: $ virsh snapshot-create-as devstack1 snap1 "f20clean-17FEB2014" \ --disk-only --diskspec hda,snapshot=external,file=/export/vmimages/overlay1.qcow2 \ --atomic 3. List it: $ virsh snapshot-list devstack1 Name Creation Time State ------------------------------------------------------------ snap1 2014-02-17 13:37:24 -0500 shutoff 4. Attempt to revert to 'snap1': $ virsh snapshot-revert devstack1 snap1 Actual results -------------- Revert fails with a totally unhelpful error: $ virsh snapshot-revert devstack1 snap1 error: An error occurred, but the cause is unknown Expected results ---------------- Some useful info, indicating that the admin is trying to perfom an operation that doesn't work yet. Additional info --------------- Disk image backing chain info via `qemu-img`: $ qemu-img info --backing-chain /export/vmimages/overlay1.qcow2 image: /export/vmimages/overlay1.qcow2 file format: qcow2 virtual size: 40G (42949672960 bytes) disk size: 11G cluster_size: 65536 backing file: /export/vmimages/fedora-20.img backing file format: raw Format specific information: compat: 1.1 lazy refcounts: false image: /export/vmimages/fedora-20.img file format: raw virtual size: 40G (42949672960 bytes) disk size: 2.2G