[SERVER-42573] Only warn about readConcernMajority enabled in primary-secondary-arbiter configuration Created: 01/Aug/19  Updated: 29/Oct/23  Resolved: 14/Oct/19

Status: Closed
Project: Core Server
Component/s: None
Affects Version/s: None
Fix Version/s: 3.6.17, 4.3.1, 4.2.3, 4.0.16

Type: Improvement Priority: Major - P3
Reporter: Miguel Angel Nieto Assignee: Xuerui Fa
Resolution: Fixed Votes: 0
Labels: neweng
Remaining Estimate: Not Specified
Time Spent: Not Specified
Original Estimate: Not Specified

Issue Links:
Backports
Related
is related to SERVER-37557 Add startup warning about enableMajor... Closed
is related to SERVER-43188 Add warnings about enableMajorityRead... Closed
Backwards Compatibility: Fully Compatible
Backport Requested:
v4.2, v4.0, v3.6
Sprint: Repl 2019-09-09
Participants:
Case:

 Description   

Hello,

The startup warning about "Read Concern Majority" is shown when the users have an arbiter, regardless of the number of nodes. If we check the documentation, it is only recommended when the replica set is PSA.

"If you are using a deployment other than a 3-member PSA, you do not need to disable read concern majority."

When the warning was created on SERVER-37557 it was decided to alert when an arbiter was present, regardless on the replica set configuration:

"the risk exists in any set with an arbiter, since they allow you to accept writes when the majority commit point cannot move forward. We are going to recommend all sets with arbiters use enableMajorityReadConcern:"false"."

So, the warning is not following the documentation, and this could be confusing to the MongoDB users.

Regards,
Miguel.



 Comments   
Comment by Githook User [ 04/Feb/20 ]

Author:

{'name': 'Xuerui Fa', 'username': 'XueruiFa', 'email': 'xuerui.fa@mongodb.com'}

Message: SERVER-42573 Only warn about enableReadConcernMajority if PSA architecture

(cherry picked from commit 897ebf0eb55ffc68ef4c09aefc43a48bca82df3d)
Branch: v4.2
https://github.com/mongodb/mongo/commit/073da4c9ef0e5c23c3eb3e8094630191a646de58

Comment by Githook User [ 04/Feb/20 ]

Author:

{'name': 'Xuerui Fa', 'username': 'XueruiFa', 'email': 'xuerui.fa@mongodb.com'}

Message: SERVER-42573 Only warn about enableReadConcernMajority if PSA architecture

(cherry picked from commit 897ebf0eb55ffc68ef4c09aefc43a48bca82df3d)
Branch: v4.0
https://github.com/mongodb/mongo/commit/785d9ca956fabd2e7430884f5270393bd491ab5b

Comment by Githook User [ 04/Feb/20 ]

Author:

{'name': 'Xuerui Fa', 'username': 'XueruiFa', 'email': 'xuerui.fa@mongodb.com'}

Message: SERVER-42573 Only warn about enableReadConcernMajority if PSA architecture

(cherry picked from commit 897ebf0eb55ffc68ef4c09aefc43a48bca82df3d)
Branch: v3.6
https://github.com/mongodb/mongo/commit/21899f6bd537399e00dd86833d185b1ebd1fffe9

Comment by Evin Roesle [ 14/Oct/19 ]

alyson.cabral and I spoke with spencer.brown on Friday about this ticket. We discussed how the business cost of customers not being able to utilize core features when readConcernMajority disabled outweighs the support cost so we agreed to minimize the number of clusters and recommend disabling this flag. We will move forward with backporting.

Comment by Nic Cottrell [ 23/Sep/19 ]

This causes quite a few "false positives" and pushes some customers to disable RCM completely. If this is not a risky change, please backport.

Comment by Githook User [ 06/Sep/19 ]

Author:

{'username': 'XueruiFa', 'email': 'xuerui.fa@mongodb.com', 'name': 'Xuerui Fa'}

Message: SERVER-42573 Only warn about enableReadConcernMajority if PSA architecture
Branch: master
https://github.com/mongodb/mongo/commit/897ebf0eb55ffc68ef4c09aefc43a48bca82df3d

Comment by A. Jesse Jiryu Davis [ 08/Aug/19 ]

There's no way to disable the warning, but this will be fixed in the next version to warn only in PSA deployments.

Comment by SACHIN YADAV [ 08/Aug/19 ]

but i am getting warning in replica set with multiple secondary (Not PSA deployment).

will this be fixed in next version or there is a method to disable the warning .

Comment by A. Jesse Jiryu Davis [ 05/Aug/19 ]

After discussion we've decided to stick with the recommendation in the docs: we recommend users disable majority read concern in PSA deployments, but we don't have a strong recommendation for other deployments with arbiters. So we'll only show the warning in PSA.

Generated at Thu Feb 08 05:00:50 UTC 2024 using Jira 9.7.1#970001-sha1:2222b88b221c4928ef0de3161136cc90c8356a66.