SERVER-35807 Prepend _movePrimary and _cloneCatalogData internal commands with "_shardsvr".

1 files changed, 16 insertions, 1 deletions

diff --git a/src/mongo/db/s/config/configsvr_move_primary_command.cpp b/src/mongo/db/s/config/configsvr_move_primary_command.cpp
index f0272e1a92c..eea3b876e46 100644
--- a/src/mongo/db/s/config/configsvr_move_primary_command.cpp
+++ b/src/mongo/db/s/config/configsvr_move_primary_command.cpp
@@ -181,7 +181,7 @@ public:
         }
 
         ShardMovePrimary shardMovePrimaryRequest;
-        shardMovePrimaryRequest.set_movePrimary(NamespaceString(dbname));
+        shardMovePrimaryRequest.set_shardsvrMovePrimary(NamespaceString(dbname));
         shardMovePrimaryRequest.setTo(toShard->getId().toString());
 
         auto cmdResponse = uassertStatusOK(fromShard->runCommandWithFixedRetryAttempts(
@@ -192,6 +192,21 @@ public:
                 CommandHelpers::appendPassthroughFields(cmdObj, shardMovePrimaryRequest.toBSON())),
             Shard::RetryPolicy::kIdempotent));
 
+        // If the `fromShard` is on v4.2 or earlier, it will not recognize the command name
+        // _shardsvrMovePrimary. We will retry the command with the old name _movePrimary.
+        if (cmdResponse.commandStatus == ErrorCodes::CommandNotFound) {
+            ShardMovePrimary legacyShardMovePrimaryRequest;
+            legacyShardMovePrimaryRequest.set_movePrimary(NamespaceString(dbname));
+            legacyShardMovePrimaryRequest.setTo(toShard->getId().toString());
+            cmdResponse = uassertStatusOK(fromShard->runCommandWithFixedRetryAttempts(
+                opCtx,
+                ReadPreferenceSetting(ReadPreference::PrimaryOnly),
+                "admin",
+                CommandHelpers::appendMajorityWriteConcern(CommandHelpers::appendPassthroughFields(
+                    cmdObj, legacyShardMovePrimaryRequest.toBSON())),
+                Shard::RetryPolicy::kIdempotent));
+        }
+
         CommandHelpers::filterCommandReplyForPassthrough(cmdResponse.response, &result);
 
         return true;