Red Hat Bugzilla – Bug 879655
ResourceContainer can enter an inconsistent state after resource upgrade during agent startup
Last modified: 2013-09-03 10:43:32 EDT
Description of problem:
There are 2 conditions that need to be true for this to happen:
1) There must be a resource in the inventory that has not been upgraded yet (i.e. inventoried using an older version of RHQ, agent starting up with new plugins for the first time and a plugin code determines that the resource needs to be upgraded).
2) The stop() method on the resource component must throw an exception - this can happen if it uses some API that is not initialized in the resource upgrade phase - like event subsystem (this is a bug in itself, see bug 863092).
If the above conditions are true, the following will happen:
1) The component is start()ed during resource upgrade
2) Once the upgrade is processed, the resource component is restarted to pick up the new state. This will try to stop() the resource component during the InventoryManager.prepareForResourceActivation() call.
3) The stop call fails with an exception
4) The exception is handled up in the call chain, leaving the resource container in an inconsistent state:
ResourceContainer.getResourceComponentState() returns STARTED, while the resource component itself has been torn down using its stop() method (which failed, but still could have managed to put the resource component in an weird state - neither up nor down).
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Install RHQ 3.0.0, inventory an Apache server using it
2. Upgrade to RHQ 4.6.0-SNAPSHOT
3. Do plugins update on the agent prompt or restart the agent
4. Watch the agent.log for errors during resource upgrade
The apache server resource is marked down until the agent (or at least plugin container) restart.
availability reporting works
I'm quite confident the below fixes the issue - i.e. a failure in stop() can no longer put the resource container in an invalid state.
Jay, can you see anything wrong with it or does it remind you of some other areas that would need similar treatment?
Author: Lukas Krejci <email@example.com>
Date: Fri Nov 23 17:18:35 2012 +0100
[BZ 879655] - Properly deactivate the resource instead of just calling the
component's stop() method when forcing reactivation of a started component.
This will ensure the PC can't enter an inconsistent state in the case the
stop() method fails.
This change looks correct to me. There were some relatively recent changes in this code, made by myself and Ian I think, to better handle a "starting" state in the component lifecycle. This looks like an issue resulting from, or more exposed by, those changes.
Moving to ON_QA.
Bulk closing of issues in old RHQ releases that are in production for a while now.
Please open a new issue when running into an issue.