SERVER-48345 Allow users to add nodes with member id greater than 255.

4 files changed, 36 insertions, 88 deletions

diff --git a/src/mongo/db/repl/member_config.h b/src/mongo/db/repl/member_config.h
index 39fbc30750b..d6bb75622f3 100644
--- a/src/mongo/db/repl/member_config.h
+++ b/src/mongo/db/repl/member_config.h
@@ -76,14 +76,6 @@ public:
     static const std::string kConfigVoterTagName;
 
     /**
-     * Inline `kMaxUserMemberId` to allow others use
-     * the constant without linking to `member_config.cpp`.
-     *
-     * Maximum allowed member id for new nodes added by user.
-     */
-    inline static const int kMaxUserMemberId = 255;
-
-    /**
      * Construct a MemberConfig from the contents of "mcfg".
      *
      * If "mcfg" describes any tags, builds ReplSetTags for this
diff --git a/src/mongo/db/repl/member_config_test.cpp b/src/mongo/db/repl/member_config_test.cpp
index 64bafe6330c..8b52a238b16 100644
--- a/src/mongo/db/repl/member_config_test.cpp
+++ b/src/mongo/db/repl/member_config_test.cpp
@@ -89,23 +89,22 @@ TEST(MemberConfig, ParseMemberConfigId) {
     }
     // Pass cases
     {
-
         MemberConfig mc(BSON("_id" << 0 << "host"
                                    << "localhost:12345"),
                         &tagConfig);
         ASSERT_EQUALS(MemberId(0), mc.getId());
     }
     {
-        MemberConfig mc(BSON("_id" << MemberConfig::kMaxUserMemberId << "host"
+        MemberConfig mc(BSON("_id" << 255 << "host"
                                    << "localhost:12345"),
                         &tagConfig);
-        ASSERT_EQUALS(MemberId(MemberConfig::kMaxUserMemberId), mc.getId());
+        ASSERT_EQUALS(MemberId(255), mc.getId());
     }
     {
-        MemberConfig mc(BSON("_id" << (MemberConfig::kMaxUserMemberId + 1) << "host"
+        MemberConfig mc(BSON("_id" << 256 << "host"
                                    << "localhost:12345"),
                         &tagConfig);
-        ASSERT_EQUALS(MemberId(MemberConfig::kMaxUserMemberId + 1), mc.getId());
+        ASSERT_EQUALS(MemberId(256), mc.getId());
     }
 }
 
diff --git a/src/mongo/db/repl/repl_set_config_checks.cpp b/src/mongo/db/repl/repl_set_config_checks.cpp
index df7049f9d25..b768317f041 100644
--- a/src/mongo/db/repl/repl_set_config_checks.cpp
+++ b/src/mongo/db/repl/repl_set_config_checks.cpp
@@ -142,35 +142,6 @@ Status validateSingleNodeChange(const ReplSetConfig& oldConfig, const ReplSetCon
 }
 
 /**
- * Returns ErrorCodes::BadValue if the user tries to add new nodes with member id greater than
- * MemberConfig::kMaxUserMemberId(255).
- *
- * validateMemberId() will be called only for replSetReconfig and replSetInitiate commands.
- *
- * TODO SERVER-48345: Remove this method on MongoDB v4.6 as we allow users to add new nodes
- * with member id > MemberConfig::kMaxUserMemberId(255).
- */
-Status validateMemberId(const ReplSetConfig& newConfig,
-                        const ReplSetConfig& oldConfig = ReplSetConfig()) {
-    for (ReplSetConfig::MemberIterator mNew = newConfig.membersBegin();
-         mNew != newConfig.membersEnd();
-         ++mNew) {
-        auto mNewConfigId = mNew->getId().getData();
-        // Existing members are allowed to have member id greater than kMaxUserMemberId. And,
-        // it can happen only if this node was previously running on MongoDB version greater
-        // than v4.4.
-        if (oldConfig.findMemberIndexByConfigId(mNewConfigId) == -1 &&
-            mNewConfigId > MemberConfig::kMaxUserMemberId) {
-            return Status(ErrorCodes::BadValue,
-                          str::stream()
-                              << "Replica set configuration contains new members with "
-                              << "member id greater than " << MemberConfig::kMaxUserMemberId);
-        }
-    }
-    return Status::OK();
-}
-
-/**
  * Compares two initialized and validated replica set configurations, and checks to
  * see if "newConfig" is a legal successor configuration to "oldConfig".
  *
@@ -360,11 +331,6 @@ StatusWith<int> validateConfigForInitiate(ReplicationCoordinatorExternalState* e
         return StatusWith<int>(status);
     }
 
-    status = validateMemberId(newConfig);
-    if (!status.isOK()) {
-        return status;
-    }
-
     status = newConfig.checkIfWriteConcernCanBeSatisfied(newConfig.getDefaultWriteConcern());
     if (!status.isOK()) {
         return status.withContext(
@@ -415,11 +381,6 @@ Status validateConfigForReconfig(const ReplSetConfig& oldConfig,
         return status;
     }
 
-    status = validateMemberId(newConfig, oldConfig);
-    if (!status.isOK()) {
-        return status;
-    }
-
     // For non-force reconfigs, verify that the reconfig only adds or removes a single node.
     // This ensures that all quorums of the new config overlap with all quorums of the old
     // config.
diff --git a/src/mongo/db/repl/repl_set_config_checks_test.cpp b/src/mongo/db/repl/repl_set_config_checks_test.cpp
index 0b6f573cc18..efa438491b6 100644
--- a/src/mongo/db/repl/repl_set_config_checks_test.cpp
+++ b/src/mongo/db/repl/repl_set_config_checks_test.cpp
@@ -89,16 +89,15 @@ TEST_F(ServiceContextTest, ValidateConfigForInitiate_memberId) {
 
     // Config with Member id > 255.
     OID newReplSetId = OID::gen();
-    auto invalidConfig = ReplSetConfig::parseForInitiate(
-        BSON("_id"
-             << "rs0"
-             << "version" << 1 << "protocolVersion" << 1 << "members"
-             << BSON_ARRAY(BSON("_id" << (MemberConfig::kMaxUserMemberId + 1) << "host"
-                                      << "h1"))),
-        newReplSetId);
-    ASSERT_EQUALS(
-        ErrorCodes::BadValue,
-        validateConfigForInitiate(&rses, invalidConfig, getGlobalServiceContext()).getStatus());
+    auto validConfig =
+        ReplSetConfig::parseForInitiate(BSON("_id"
+                                             << "rs0"
+                                             << "version" << 1 << "protocolVersion" << 1
+                                             << "members"
+                                             << BSON_ARRAY(BSON("_id" << 256 << "host"
+                                                                      << "h1"))),
+                                        newReplSetId);
+    ASSERT_OK(validateConfigForInitiate(&rses, validConfig, getGlobalServiceContext()).getStatus());
 }
 
 TEST_F(ServiceContextTest, ValidateConfigForInitiate_MustFindSelf) {
@@ -341,36 +340,33 @@ TEST_F(ServiceContextTest, ValidateConfigForReconfig_memberId) {
                                           << "version" << 1 << "protocolVersion" << 1 << "members"
                                           << BSON_ARRAY(BSON("_id" << 1 << "host"
                                                                    << "h1"))));
-    newConfig = ReplSetConfig::parse(
-        BSON("_id"
-             << "rs0"
-             << "version" << 2 << "protocolVersion" << 1 << "members"
-             << BSON_ARRAY(BSON("_id" << 1 << "host"
-                                      << "h1")
-                           << BSON("_id" << (MemberConfig::kMaxUserMemberId + 1) << "host"
-                                         << "h2"))));
+    newConfig = ReplSetConfig::parse(BSON("_id"
+                                          << "rs0"
+                                          << "version" << 2 << "protocolVersion" << 1 << "members"
+                                          << BSON_ARRAY(BSON("_id" << 1 << "host"
+                                                                   << "h1")
+                                                        << BSON("_id" << 256 << "host"
+                                                                      << "h2"))));
     ASSERT_OK(oldConfig.validate());
     ASSERT_OK(newConfig.validate());
-    ASSERT_EQUALS(ErrorCodes::BadValue, validateConfigForReconfig(oldConfig, newConfig, false));
+    ASSERT_OK(validateConfigForReconfig(oldConfig, newConfig, false));
 
     // Case 2: Change the member config setting for the existing member with member id > 255.
-    oldConfig = ReplSetConfig::parse(
-        BSON("_id"
-             << "rs0"
-             << "version" << 1 << "protocolVersion" << 1 << "members"
-             << BSON_ARRAY(BSON("_id" << 1 << "host"
-                                      << "h1")
-                           << BSON("_id" << (MemberConfig::kMaxUserMemberId + 1) << "host"
-                                         << "h2"))));
-    newConfig = ReplSetConfig::parse(
-        BSON("_id"
-             << "rs0"
-             << "version" << 2 << "protocolVersion" << 1 << "members"
-             << BSON_ARRAY(BSON("_id" << 1 << "host"
-                                      << "h1")
-                           << BSON("_id" << (MemberConfig::kMaxUserMemberId + 1) << "host"
-                                         << "h2"
-                                         << "priority" << 0))));
+    oldConfig = ReplSetConfig::parse(BSON("_id"
+                                          << "rs0"
+                                          << "version" << 1 << "protocolVersion" << 1 << "members"
+                                          << BSON_ARRAY(BSON("_id" << 1 << "host"
+                                                                   << "h1")
+                                                        << BSON("_id" << 256 << "host"
+                                                                      << "h2"))));
+    newConfig = ReplSetConfig::parse(BSON("_id"
+                                          << "rs0"
+                                          << "version" << 2 << "protocolVersion" << 1 << "members"
+                                          << BSON_ARRAY(BSON("_id" << 1 << "host"
+                                                                   << "h1")
+                                                        << BSON("_id" << 256 << "host"
+                                                                      << "h2"
+                                                                      << "priority" << 0))));
     ASSERT_OK(oldConfig.validate());
     ASSERT_OK(newConfig.validate());
     ASSERT_OK(validateConfigForReconfig(oldConfig, newConfig, false));