Questions about Default Read/Write Concern settings

Hi, found the Read & Write Concern setting is always fixed to majority as shown below.

[mongos] admin> db.getSiblingDB('config').settings.find()
    _id: 'ReadWriteConcernDefaults',
    defaultReadConcern: { level: 'majority' },
    defaultWriteConcern: { w: 'majority', wtimeout: 0 },
    updateOpTime: Timestamp({ t: 1720601017, i: 2 }),
    updateWallClockTime: ISODate('2024-07-10T08:43:38.054Z')

Even though I tried changing the default concern by executing the setDefaultRWConcern command, the setting changed to majority after a few seconds.

> db.adminCommand({
 "setDefaultRWConcern" : 1,
 "defaultReadConcern" : { "level" : "local" }

Is this an intended behavior involving operator intervention?

Hello @Case,

it is not something that we jumps out right away. We will investigate a bit more and update you. Is it a time pressing issue for you?

Also don’t really recommend to run MongoDB 4.4 version as it is EOL.

Thank you for answer.

Most of us in the company are still using 4.4 and are planning to upgrade soon!

The Default Concern issue is not urgent, but when migrating from our existing on-premises MongoDB (level:local and w:1) to PSMDB, we may experience increased latency in our application.