Bug 1470566

Summary: [RFE] Support changing from distribute to replicate with no active client operations
Product: [Red Hat Storage] Red Hat Gluster Storage Reporter: Sahina Bose <sabose>
Component: replicateAssignee: Ravishankar N <ravishankar>
Status: CLOSED ERRATA QA Contact: Vijay Avuthu <vavuthu>
Severity: medium Docs Contact:
Priority: medium    
Version: rhgs-3.3CC: amukherj, pkarampu, ravishankar, rcyriac, rhinduja, rhs-bugs, srmukher, storage-qa-internal
Target Milestone: ---Keywords: FutureFeature
Target Release: RHGS 3.4.0   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: glusterfs-3.12.2-1 Doc Type: Enhancement
Doc Text:
You can now convert from plain distribute to a distributed-replicate volume by using the 'gluster volume add-brick` command, provided there is no I/O happening from the client.
 Story Points: ---
Clone Of: Environment:
Last Closed: 2018-09-04 06:34:19 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: 1503132    

Description Sahina Bose 2017-07-13 08:38:28 UTC 
Description of problem:

For one of the VM store use-cases, we want to start with a single node gluster volume and then later change to replica 3 gluster volume for redundancy.

This operation should be supported, and the heal should happen automatically when user sets a replica count and adds the additional bricks.


How reproducible:
NA
Comment 1 Atin Mukherjee 2017-07-18 04:27:23 UTC 
T
Comment 3 Ravishankar N 2017-07-18 04:33:18 UTC 
No, it should work fine, especially since https://bugzilla.redhat.com/show_bug.cgi?id=1276203 has been fixed.
Comment 4 Ravishankar N 2017-07-18 07:36:57 UTC 
Realised that there is a corner case: BZ 1400092
Comment 7 Vijay Avuthu 2018-03-02 06:10:32 UTC 
Update:
=========

> tried below scenario

1) create  1 * 1 volume on a single node
2) create different IO which consists of
Comment 10 Vijay Avuthu 2018-03-12 10:28:49 UTC 
Update :
============

> Covered below scenarios as well.

Scenario 1: converting 1 * 1 to 1 * 3

Steps:
 
1) create 1 * 1 distribute volume and start
2) create files and dirs from client ( 13k files and 13k dirs )
3) add bricks to volume so that it will convert to 1 * 3 ( Replicate )
4) Monitor the heal completion.
5) arequal-checksum is same on all the bricks and equals to arequal-checksum of client mountpoint


Scenario 1: converting 2 * 1 to 2 * 3

1) create 2 * 1 distribute volume and start
2) create files and dirs from client ( 13k files and 13k dirs )
3) add bricks to volume so that it will convert to 2 * 3 ( Distributed-Replicate )
4) Monitor the heal completion.
5) arequal-checksum is same on all the bricks in the replica set


Changing status to Verified.
Comment 13 errata-xmlrpc 2018-09-04 06:34:19 UTC 
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://access.redhat.com/errata/RHSA-2018:2607