Bug 1262161

Summary: RFE : Feature: Automagic unsplit-brain policies for v3.6.x (cluster/afr)
Product: [Community] GlusterFS Reporter: rwareing
Component: replicateAssignee: rwareing
Status: CLOSED NEXTRELEASE QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: 3.6.6CC: bugs, sshreyas
Target Milestone: ---Keywords: FutureFeature, Triaged
Target Release: ---   
Hardware: All   
OS: All   
Whiteboard:
Fixed In Version: Doc Type: Enhancement
Doc Text:
Story Points: ---
Clone Of:
: 1328224 (view as bug list) Environment:
Last Closed: 2016-08-23 12:30:30 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: 1328224, 1339639    
Attachments:
Description Flags
Patch to add automagic split-brain resolution. none

Description rwareing 2015-09-11 01:57:29 UTC
Created attachment 1072407 [details]
Patch to add automagic split-brain resolution.

Description of problem:
From time to time, GlusterFS users, admins (and even developers) can do unfortunate things to a volume which cause split-brain to files and directories.  In such cases where the so-called "wise fool" algorithm (aka change logs) cannot determine a clean version of the file an IO error will be bubbled up to the user; thus ruining their GlusterFS clustered storage experience.

The present solution for these cases is to go into the backend and delete or move the copies of the file that aren't desired, or "pinning" to a specific replica index (which is basically choosing randomly).  For large scale installations of GlusterFS this really isn't a workable solution, and quite often a simple heuristic based on time, size or majority will suffice to resolve things automagically to most end-users satisfaction.

This patch introduces policy based split-brain resolution.

Version-Release number of selected component (if applicable):
v3.6.x

How reproducible:
100%

Steps to Reproduce:
N/A

Actual results:
N/A

Expected results:
N/A

Additional info:
N/A

Comment 1 rwareing 2015-09-11 02:12:46 UTC
Also, to be clear this patch should patch cleanly to the release-3.6 branch.

Comment 2 Niels de Vos 2016-08-23 12:30:30 UTC
This bug is being closed as GlusterFS-3.6 is nearing its End-Of-Life and only important security bugs will be fixed. This bug has been fixed in more recent GlusterFS releases. If you still face this bug with the newer GlusterFS versions, please open a new bug.