Description of problem: At the moment we are lacking of an easy tool to activate an image chain on block domains (including the required symlinks for the backing files to work). This could also simplify the integration with third party tools that are relying on libguestfs. It should be simple enough to expose the current prepareImage and teardownImage commands in vdsClient. In the long run the preferred way to integrate would be through the image fleecing API.
what's the level of concern of an LV chain active across multiple hosts? behavior when a host sees an already active LV? level of effort to do this? an HSM verb i assume?
(In reply to Itamar Heim from comment #2) > what's the level of concern of an LV chain active across multiple hosts? There's no problem in activating the same chain on multiple hosts (as long as there's no concurrent access to the content). Things that are problematic: - read the content of the active layer if the vm is up (inconsistent) or writing data in the backing volumes corrupting the chain (these are not specific to lvm, they're true for file domains as well) - if the volume chain is left active (no teardown) and a cold merge takes place on another host then at least one of the old active volumes may be using wrong segments (possible corruption if the vm is then started on this host) > behavior when a host sees an already active LV? Partially answered above. We have to clearly state that teardownImage must be issued. Anyway if there was no cold merge executed on another host then we're ok. Anyway all this mumbo-jumbo related to teardownImage can be finally resolved if we issue an lvrefresh in case the lv is already active (food for another rfe). > level of effort to do this? Low, just expose the verbs in the xml-rpc bindings and in vdsClient. > an HSM verb i assume? Yes, but they already exist... we just need to expose them.
Works for my use case described in #1104672. Thanks!
Yeela, these patches are included in v4.16.0. Can you please explain why you returned this BZ to MODIFIED?
Added External Tracker to Test Plan 6099
Completed Test Plan Added External Tracker Added "Done" to QA Whiteboard
TCMS plan was executed: https://tcms.engineering.redhat.com/run/163705/ 2 bugs were filed: https://bugzilla.redhat.com/show_bug.cgi?id=1131160 https://bugzilla.redhat.com/show_bug.cgi?id=1130995 Verified using ovirt-3.5 RC1
Fede, can you provide some doctext here please?
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://rhn.redhat.com/errata/RHBA-2015-0159.html