SERVER-69299 Shard Merge to enforce backupCursorCheckpointTimestamp

1 files changed, 12 insertions, 1 deletions

diff --git a/src/mongo/db/repl/tenant_migration_recipient_service.cpp b/src/mongo/db/repl/tenant_migration_recipient_service.cpp
index 75ebc74f64c..9c9038c3846 100644
--- a/src/mongo/db/repl/tenant_migration_recipient_service.cpp
+++ b/src/mongo/db/repl/tenant_migration_recipient_service.cpp
@@ -1013,6 +1013,8 @@ SemiFuture<void> TenantMigrationRecipientService::Instance::_openBackupCursor(
         return aggRequest.toBSON(BSONObj());
     }();
 
+    auto startMigrationDonorTimestamp = _stateDoc.getStartMigrationDonorTimestamp();
+
     auto fetchStatus = std::make_shared<boost::optional<Status>>();
     auto uniqueMetadataInfo = std::make_unique<boost::optional<shard_merge_utils::MetadataInfo>>();
     auto fetcherCallback =
@@ -1021,7 +1023,8 @@ SemiFuture<void> TenantMigrationRecipientService::Instance::_openBackupCursor(
             self = shared_from_this(),
             fetchStatus,
             metadataInfoPtr = uniqueMetadataInfo.get(),
-            token
+            token,
+            startMigrationDonorTimestamp
         ](const Fetcher::QueryResponseStatus& dataStatus,
           Fetcher::NextAction* nextAction,
           BSONObjBuilder* getMoreBob) noexcept {
@@ -1045,6 +1048,14 @@ SemiFuture<void> TenantMigrationRecipientService::Instance::_openBackupCursor(
                                "backupCursorId"_attr = data.cursorId,
                                "backupCursorCheckpointTimestamp"_attr = checkpointTimestamp);
 
+                    // This ensures that the recipient won’t receive any 2 phase index build donor
+                    // oplog entries during the migration. We also have a check in the tenant oplog
+                    // applier to detect such oplog entries. Adding a check here helps us to detect
+                    // the problem earlier.
+                    uassert(6929900,
+                            "backupCursorCheckpointTimestamp should be greater than or equal to "
+                            "startMigrationDonorTimestamp",
+                            checkpointTimestamp >= startMigrationDonorTimestamp);
                     {
                         stdx::lock_guard lk(_mutex);
                         stdx::lock_guard<TenantMigrationSharedData> sharedDatalk(*_sharedData);