1 files changed, 39 insertions, 25 deletions
diff --git a/src/mongo/db/db.cpp b/src/mongo/db/db.cpp
index 92049d1f2a6..e18b60efb17 100644
--- a/src/mongo/db/db.cpp
+++ b/src/mongo/db/db.cpp
@@ -679,32 +679,46 @@ static void _initAndListen(int listenPort) {
 #ifndef _WIN32
         mongo::signalForkSuccess();
 #endif
+        AuthorizationManager* globalAuthzManager = getGlobalAuthorizationManager();
+        if (globalAuthzManager->shouldValidateAuthSchemaOnStartup()) {
+            Status status = authindex::verifySystemIndexes(startupOpCtx.get());
+            if (!status.isOK()) {
+                log() << status.reason();
+                exitCleanly(EXIT_NEED_UPGRADE);
+            }
 
-        Status status = authindex::verifySystemIndexes(startupOpCtx.get());
-        if (!status.isOK()) {
-            log() << status.reason();
-            exitCleanly(EXIT_NEED_UPGRADE);
-        }
-
-        // SERVER-14090: Verify that auth schema version is schemaVersion26Final.
-        int foundSchemaVersion;
-        status = getGlobalAuthorizationManager()->getAuthorizationVersion(startupOpCtx.get(),
-                                                                          &foundSchemaVersion);
-        if (!status.isOK()) {
-            log() << "Auth schema version is incompatible: "
-                  << "User and role management commands require auth data to have "
-                  << "at least schema version " << AuthorizationManager::schemaVersion26Final
-                  << " but startup could not verify schema version: " << status.toString() << endl;
-            exitCleanly(EXIT_NEED_UPGRADE);
-        }
-        if (foundSchemaVersion < AuthorizationManager::schemaVersion26Final) {
-            log() << "Auth schema version is incompatible: "
-                  << "User and role management commands require auth data to have "
-                  << "at least schema version " << AuthorizationManager::schemaVersion26Final
-                  << " but found " << foundSchemaVersion << ". In order to upgrade "
-                  << "the auth schema, first downgrade MongoDB binaries to version "
-                  << "2.6 and then run the authSchemaUpgrade command." << endl;
-            exitCleanly(EXIT_NEED_UPGRADE);
+            // SERVER-14090: Verify that auth schema version is schemaVersion26Final.
+            int foundSchemaVersion;
+            status = globalAuthzManager->getAuthorizationVersion(startupOpCtx.get(),
+                                                                 &foundSchemaVersion);
+            if (!status.isOK()) {
+                log() << "Auth schema version is incompatible: "
+                      << "User and role management commands require auth data to have "
+                      << "at least schema version " << AuthorizationManager::schemaVersion26Final
+                      << " but startup could not verify schema version: " << status.toString()
+                      << endl;
+                exitCleanly(EXIT_NEED_UPGRADE);
+            }
+            if (foundSchemaVersion < AuthorizationManager::schemaVersion26Final) {
+                log() << "Auth schema version is incompatible: "
+                      << "User and role management commands require auth data to have "
+                      << "at least schema version " << AuthorizationManager::schemaVersion26Final
+                      << " but found " << foundSchemaVersion << ". In order to upgrade "
+                      << "the auth schema, first downgrade MongoDB binaries to version "
+                      << "2.6 and then run the authSchemaUpgrade command." << endl;
+                exitCleanly(EXIT_NEED_UPGRADE);
+            }
+        } else if (globalAuthzManager->isAuthEnabled()) {
+            error() << "Auth must be disabled when starting without auth schema validation";
+            exitCleanly(EXIT_BADOPTIONS);
+        } else {
+            // If authSchemaValidation is disabled and server is running without auth,
+            // warn the user and continue startup without authSchema metadata checks.
+            log() << startupWarningsLog;
+            log() << "** WARNING: Startup auth schema validation checks are disabled for the "
+                     "database." << startupWarningsLog;
+            log() << "**          This mode should only be used to manually repair corrupted auth "
+                     "data." << startupWarningsLog;
         }
 
         getDeleter()->startWorkers();