SERVER-61027 Add permitMigration flag to prevent balancer rounds and migrations commit

5 files changed, 49 insertions, 2 deletions

diff --git a/jstests/sharding/move_chunk_allowMigrations.js b/jstests/sharding/move_chunk_allowMigrations.js
index 1ef488f7f33..4db3d97b946 100644
--- a/jstests/sharding/move_chunk_allowMigrations.js
+++ b/jstests/sharding/move_chunk_allowMigrations.js
@@ -62,6 +62,38 @@ const setUpDb = function setUpDatabaseAndEnableSharding() {
     assert.eq(false, cachedEntry.allowMigrations);
 })();
 
+// TODO SERVER-61033: remove after permitMigrations have been merged with allowMigrations.
+// Tests that moveChunk does not succeed when {permitMigrations: false}
+(function testPermitMigrationsFalsePreventsMoveChunk() {
+    setUpDb();
+
+    const collName = "collA";
+    const ns = dbName + "." + collName;
+
+    assert.commandWorked(st.s.getDB(dbName).getCollection(collName).insert({_id: 0}));
+    assert.commandWorked(st.s.getDB(dbName).getCollection(collName).insert({_id: 1}));
+    assert.commandWorked(st.s.adminCommand({shardCollection: ns, key: {_id: 1}}));
+
+    // Confirm that an inProgress moveChunk fails once {allowMigrations: false}
+    const fp = configureFailPoint(st.shard0, "moveChunkHangAtStep4");
+    const awaitResult = startParallelShell(
+        funWithArgs(function(ns, toShardName) {
+            assert.commandFailedWithCode(
+                db.adminCommand({moveChunk: ns, find: {_id: 0}, to: toShardName}),
+                ErrorCodes.ConflictingOperationInProgress);
+        }, ns, st.shard1.shardName), st.s.port);
+    fp.wait();
+    assert.commandWorked(configDB.collections.updateOne(
+        {_id: ns}, {$set: {permitMigrations: false}}, {writeConcern: {w: "majority"}}));
+    fp.off();
+    awaitResult();
+
+    // {permitMigrations: false} is set, sending a new moveChunk command should also fail.
+    assert.commandFailedWithCode(
+        st.s.adminCommand({moveChunk: ns, find: {_id: 0}, to: st.shard1.shardName}),
+        ErrorCodes.ConflictingOperationInProgress);
+})();
+
 // Tests {allowMigrations: false} disables balancing for collB and does not interfere with balancing
 // for collA.
 //
@@ -206,6 +238,9 @@ testBalancer(false /* allowMigrations */, {});
 testBalancer(false /* allowMigrations */, {noBalance: false});
 testBalancer(false /* allowMigrations */, {noBalance: true});
 
+// TODO SERVER-61033: merge permitMigrations with allowMigrations.
+testBalancer(true /* allowMigrations */, {permitMigrations: false});
+
 // Test the _configsvrSetAllowMigrations internal command
 testConfigsvrSetAllowMigrationsCommand();
 
diff --git a/src/mongo/db/s/balancer/balancer_chunk_selection_policy_impl.cpp b/src/mongo/db/s/balancer/balancer_chunk_selection_policy_impl.cpp
index 0f2349e84a6..f139d1d8f14 100644
--- a/src/mongo/db/s/balancer/balancer_chunk_selection_policy_impl.cpp
+++ b/src/mongo/db/s/balancer/balancer_chunk_selection_policy_impl.cpp
@@ -351,7 +351,7 @@ StatusWith<MigrateInfoVector> BalancerChunkSelectionPolicyImpl::selectChunksToMo
     for (const auto& coll : collections) {
         const NamespaceString& nss(coll.getNss());
 
-        if (!coll.getAllowBalance() || !coll.getAllowMigrations()) {
+        if (!coll.getAllowBalance() || !coll.getAllowMigrations() || !coll.getPermitMigrations()) {
             LOGV2_DEBUG(21851,
                         1,
                         "Not balancing collection {namespace}; explicitly disabled.",
diff --git a/src/mongo/db/s/config/sharding_catalog_manager_chunk_operations.cpp b/src/mongo/db/s/config/sharding_catalog_manager_chunk_operations.cpp
index 870a6bc6392..740da8d9e59 100644
--- a/src/mongo/db/s/config/sharding_catalog_manager_chunk_operations.cpp
+++ b/src/mongo/db/s/config/sharding_catalog_manager_chunk_operations.cpp
@@ -908,7 +908,7 @@ StatusWith<BSONObj> ShardingCatalogManager::commitChunkMigration(
     const CollectionType coll(findCollResponse.docs[0]);
     uassert(ErrorCodes::ConflictingOperationInProgress,
             "Collection is undergoing changes and chunks cannot be moved",
-            coll.getAllowMigrations());
+            coll.getAllowMigrations() && coll.getPermitMigrations());
 
     const auto findChunkQuery = BSON(ChunkType::collectionUUID() << coll.getUuid());
 
diff --git a/src/mongo/s/catalog/type_collection.h b/src/mongo/s/catalog/type_collection.h
index 05b0e5ed610..f7d5641ec80 100644
--- a/src/mongo/s/catalog/type_collection.h
+++ b/src/mongo/s/catalog/type_collection.h
@@ -168,6 +168,11 @@ public:
             setPre50CompatibleAllowMigrations(false);
     }
 
+    // TODO SERVER-61033: remove after permitMigrations have been merge with allowMigrations.
+    bool getPermitMigrations() const {
+        return CollectionTypeBase::getPermitMigrations().get_value_or(true);
+    }
+
     SupportingLongNameStatusEnum getSupportingLongName() const;
 
     void setSupportingLongName(SupportingLongNameStatusEnum value);
diff --git a/src/mongo/s/catalog/type_collection.idl b/src/mongo/s/catalog/type_collection.idl
index d9e77d48b4e..118f08ec15c 100644
--- a/src/mongo/s/catalog/type_collection.idl
+++ b/src/mongo/s/catalog/type_collection.idl
@@ -166,3 +166,10 @@ structs:
                               sharded collection UUID, instead of the namespace, as part of their
                               names, i.e., system.cache.chunks.<UUID>."
                 optional: true
+# TODO SERVER-61033: merge this flag with allowMigrations.
+            permitMigrations:
+                type: bool
+                description: "DEPRECATED flag that determines wether this collection allows chunks to
+                               move. This will only prevent migration from committing and new balancer
+                               rounds, this flag will not be loaded by shards."
+                optional: true
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