Bug 1090511

Summary:	OVIRT35 - [RFE] Improve fencing robustness by retrying failed attempts
Product:	[Retired] oVirt	Reporter:	Oved Ourfali <oourfali>
Component:	ovirt-engine-core	Assignee:	Eli Mesika <emesika>
Status:	CLOSED CURRENTRELEASE	QA Contact:	sefi litmanovich <slitmano>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	3.5	CC:	gklein, iheim, rbalakri, s.kieske, yeylon
Target Milestone:	---	Keywords:	FutureFeature
Target Release:	3.5.0
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:	infra
Fixed In Version:		Doc Type:	Enhancement
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2014-10-17 12:41:32 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	Infra	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	1129381
Bug Blocks:	961753

Description Oved Ourfali 2014-04-23 13:44:52 UTC

Currently when a hypervisor becomes unresponsive and has to be fenced only one other host (the "fence proxy") within the cluster is responsible of fencing it. Moreover, if the fencing action fails for some reason, it's not re-attempted - leaving the victim host as unresponsive and requiring manual intervention.

The request here is to improve the robustness of fencing. If a fencing attempt fails (e.g. temporary communication problem between the chosen proxy host and the victim's PM), then re-attempt the fencing action, and/or attempt it from a different host. 

The "fence proxy" might have some connectivity problems to the victim's power management system, but it could well be that other hosts can access it and succeed at fencing. Also, some of these failures are transient.

Failing at first attempt and not re-trying requires manual operator intervention. While we wait for this to happen, we could keep trying from other hosts.

Comment 1 Sven Kieske 2014-04-23 14:00:28 UTC

Additional idea:
Why not make it configurable what should happen when fencing fails
the first time?
Or include some kind of default policy configuration for fencing
via a configuration file, which can be edited by users to their needs?

Comment 2 Sandro Bonazzola 2014-10-17 12:41:32 UTC

oVirt 3.5 has been released and should include the fix for this issue.