Bug 1643370

Summary: [geo-rep]: RFE - Make slave volume read-only while setting up geo-rep (by default)
Product: [Red Hat Storage] Red Hat Gluster Storage Reporter: Rochelle <rallan>
Component: geo-replicationAssignee: Harpreet Kaur Lalwani <hlalwani>
Status: CLOSED ERRATA QA Contact: Rochelle <rallan>
Severity: high Docs Contact:
Priority: medium    
Version: rhgs-3.4CC: avishwan, csaba, hlalwani, khiremat, nchilaka, rhs-bugs, sanandpa, sankarshan, sheggodu, srmukher, storage-qa-internal, sunkumar
Target Milestone: ---Keywords: EasyFix, FutureFeature, RFE, ZStream
Target Release: RHGS 3.4.z Batch Update 3   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard:
Fixed In Version: glusterfs-3.12.2-33 Doc Type: Release Note
Doc Text:
With this release, while setting up geo-replication, the slave volumes are made read-only by default. The intention is to write to the master and have the slave volumes synced to it. Considering write should not happen from the slave, it is competent to make the slave volumes read-only.
 Story Points: ---
Clone Of:
: 1654187 (view as bug list) Environment:
Last Closed: 2019-02-04 07:41:25 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: 1654187    

Description Rochelle 2018-10-26 06:26:27 UTC 
Description of problem:
=======================
As of now, if we want to make a volume as read-only, we need to specify the volume option and enable it using:

gluster volume set <volume_name> features.read-only on

In geo-rep, the main idea is to write to the master and that is synced to the slave. Since writes should not happen from the slave, it is good to make the slave as read-only by default to avoid mishaps.

In the event of a failover/failback scenario where the slave is made the master and writes need to happen from the slave, this read-only option should simply be disabled (along with enabling the other options which enable the slave volume to sync to the original master)
Comment 3 Nag Pavan Chilakam 2018-11-28 11:28:36 UTC 
proposing this for 3.4.3 as the fix helps in avoiding cases from customer(otherwise accidentally then can do destructive action on slave side, and lead to bad experience)
Comment 15 Srijita Mukherjee 2019-01-20 19:21:00 UTC 
The doc text has been updated. Kindly review the technical accuracy.
Comment 16 Sunny Kumar 2019-02-01 04:27:07 UTC 
Doc text looks good.
Comment 18 errata-xmlrpc 2019-02-04 07:41:25 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/RHBA-2019:0263