SERVER-57373 Add new startup warning around eMRC=F removal

3 files changed, 9 insertions, 3 deletions

diff --git a/jstests/noPassthrough/devnull.js b/jstests/noPassthrough/devnull.js
index 5d3fa5e1c5f..8405cd57751 100644
--- a/jstests/noPassthrough/devnull.js
+++ b/jstests/noPassthrough/devnull.js
@@ -3,7 +3,7 @@ const emrcFalseConn =
     MongoRunner.runMongod({storageEngine: "devnull", enableMajorityReadConcern: false});
 assert(!emrcFalseConn);
 var logContents = rawMongoProgramOutput();
-assert(logContents.indexOf("enableMajorityReadConcern:false is no longer supported") > 0);
+assert(logContents.search(/5324700.*Starting in 5.0, disabling enableMajorityReadConcern/) > 0);
 
 // Even though enableMajorityReadConcern: true is the default, the server internally changes
 // this value to false when running with the devnull storage engine.
diff --git a/jstests/noPassthrough/supports_read_concern_majority.js b/jstests/noPassthrough/supports_read_concern_majority.js
index 64cc5b7dad1..5163215e2da 100644
--- a/jstests/noPassthrough/supports_read_concern_majority.js
+++ b/jstests/noPassthrough/supports_read_concern_majority.js
@@ -13,7 +13,7 @@ if (storageEngine === "wiredTiger" || storageEngine === "inMemory") {
     const conn = MongoRunner.runMongod({enableMajorityReadConcern: false});
     assert(!conn);
     var logContents = rawMongoProgramOutput();
-    assert(logContents.indexOf("enableMajorityReadConcern:false is no longer supported") > 0);
+    assert(logContents.search(/5324700.*Starting in 5.0, disabling enableMajorityReadConcern/) > 0);
     return;
 }
 
diff --git a/src/mongo/db/mongod_options.cpp b/src/mongo/db/mongod_options.cpp
index fc9ef7edeb3..1b119db13c6 100644
--- a/src/mongo/db/mongod_options.cpp
+++ b/src/mongo/db/mongod_options.cpp
@@ -146,7 +146,13 @@ bool handlePreValidationMongodOptions(const moe::Environment& params,
 
     if (params.count("replication.enableMajorityReadConcern") &&
         params["replication.enableMajorityReadConcern"].as<bool>() == false) {
-        LOGV2_FATAL_CONTINUE(5324700, "enableMajorityReadConcern:false is no longer supported");
+        LOGV2_FATAL_CONTINUE(
+            5324700,
+            "** ERROR: Starting in 5.0, disabling enableMajorityReadConcern setting "
+            "is no longer available because of MongoDB's resiliency enhancements. If "
+            "your environment was previously running with eMRC=f, please see "
+            "https://docs.mongodb.com/v5.0/reference/read-concern-majority/"
+            "#disable-read-concern-majority");
         return false;
     }