1 files changed, 14 insertions, 72 deletions

diff --git a/src/mongo/db/repl/topology_coordinator.cpp b/src/mongo/db/repl/topology_coordinator.cpp
index 630fefa541c..47a043e093e 100644
--- a/src/mongo/db/repl/topology_coordinator.cpp
+++ b/src/mongo/db/repl/topology_coordinator.cpp
@@ -267,23 +267,8 @@ void TopologyCoordinator::_setSyncSource(HostAndPort newSyncSource,
 HostAndPort TopologyCoordinator::chooseNewSyncSource(Date_t now,
                                                      const OpTime& lastOpTimeFetched,
                                                      ReadPreference readPreference) {
-    // If we are not a member of the current replica set configuration, no sync source is valid.
-    if (_selfIndex == -1) {
-        LOGV2_DEBUG(
-            21778, 1, "Cannot sync from any members because we are not in the replica set config");
-        return HostAndPort();
-    }
-
-    // Check to see if we should choose a sync source because 'unsupportedSyncSource' was
-    // set.
-    auto maybeSyncSource = _chooseSyncSourceUnsupportedSyncSourceParameter(now);
-    if (maybeSyncSource) {
-        _setSyncSource(*maybeSyncSource, now, false /* fromReplSetSyncFrom */);
-        return _syncSource;
-    }
-
     // Check to see if we should choose a sync source because the 'replSetSyncFrom' command was set.
-    maybeSyncSource = _chooseSyncSourceReplSetSyncFrom(now);
+    auto maybeSyncSource = _chooseSyncSourceReplSetSyncFrom(now);
     if (maybeSyncSource) {
         // If we have a forced sync source via 'replSetSyncFrom', set the _replSetSyncFromSet flag
         // to true.
@@ -541,7 +526,9 @@ bool TopologyCoordinator::_isEligibleSyncSource(int candidateIndex,
 }
 
 boost::optional<HostAndPort> TopologyCoordinator::_chooseSyncSourceReplSetSyncFrom(Date_t now) {
-    invariant(_selfIndex != -1, "Unexpectedly not in the replica set config");
+    if (_selfIndex == -1) {
+        return boost::none;
+    }
 
     if (_forceSyncSourceIndex == -1) {
         return boost::none;
@@ -557,43 +544,13 @@ boost::optional<HostAndPort> TopologyCoordinator::_chooseSyncSourceReplSetSyncFr
     return syncSource;
 }
 
-boost::optional<HostAndPort> TopologyCoordinator::_chooseSyncSourceUnsupportedSyncSourceParameter(
-    Date_t now) {
-    invariant(_selfIndex != -1, "Unexpectedly not in the replica set config");
-
-    auto syncSourceStr = repl::unsupportedSyncSource;
-    if (syncSourceStr.empty()) {
-        return boost::none;
-    }
-    auto syncSource = HostAndPort(syncSourceStr);
-    const int syncSourceIndex = _rsConfig.findMemberIndexByHostAndPort(syncSource);
-    if (syncSourceIndex < 0) {
-        LOGV2_FATAL(
-            7785600,
-            "Selecting node specified in 'unsupportedSyncSource' parameter failed due to host "
-            "and port not in replica set config.",
-            "unsupportedSyncSource"_attr = syncSourceStr);
-    }
-
-    if (_selfIndex == syncSourceIndex) {
-        LOGV2_FATAL(
-            7785601,
-            "Node specified in 'unsupportedSyncSource' parameter is self: cannot select self as "
-            "a sync source",
-            "unsupportedSyncSource"_attr = syncSourceStr);
-    }
-
-    LOGV2(7785602,
-          "Choosing sync source candidate specified by 'unsupportedSyncSource' parameter",
-          "syncSource"_attr = syncSourceStr,
-          "syncsourceobj"_attr = syncSource);
-    std::string msg(str::stream() << "syncing from: " << syncSourceStr << " by request");
-    setMyHeartbeatMessage(now, msg);
-    return syncSource;
-}
-
 boost::optional<HostAndPort> TopologyCoordinator::_chooseSyncSourceInitialChecks(Date_t now) {
-    invariant(_selfIndex != -1, "Unexpectedly not in the replica set config");
+    // If we are not a member of the current replica set configuration, no sync source is valid.
+    if (_selfIndex == -1) {
+        LOGV2_DEBUG(
+            21778, 1, "Cannot sync from any members because we are not in the replica set config");
+        return HostAndPort();
+    }
 
     if (auto sfp = forceSyncSourceCandidate.scoped(); MONGO_unlikely(sfp.isActive())) {
         const auto& data = sfp.getData();
@@ -748,13 +705,6 @@ void TopologyCoordinator::prepareSyncFromResponse(const HostAndPort& target,
         return;
     }
 
-    if (!repl::unsupportedSyncSource.empty()) {
-        *result =
-            Status(ErrorCodes::IllegalOperation,
-                   "replSetSyncFrom may not be used when 'unsupportedSyncSource' parameter is set");
-        return;
-    }
-
     ReplSetConfig::MemberIterator targetConfig = _rsConfig.membersEnd();
     int targetIndex = 0;
     for (ReplSetConfig::MemberIterator it = _rsConfig.membersBegin(); it != _rsConfig.membersEnd();
@@ -3161,13 +3111,6 @@ TopologyCoordinator::_shouldChangeSyncSourceInitialChecks(const HostAndPort& cur
         return {ChangeSyncSourceDecision::kNo, -1};
     }
 
-    if (!repl::unsupportedSyncSource.empty()) {
-        LOGV2(7785604,
-              "Not choosing new sync source because sync source is forced via "
-              "'unsupportedSyncSource' parameter");
-        return {ChangeSyncSourceDecision::kNo, -1};
-    }
-
     // If the user requested a sync source change, return kYes.
     if (_forceSyncSourceIndex != -1) {
         LOGV2(21829,
@@ -3361,11 +3304,10 @@ bool TopologyCoordinator::shouldChangeSyncSourceDueToPingTime(const HostAndPort&
     // If we find an eligible sync source that is significantly closer than our current sync source,
     // return true.
 
-    // Do not re-evaluate our sync source if it was set via the replSetSyncFrom command, the
-    // forceSyncSourceCandidate failpoint, or the 'unsupportedSyncSource' server parameter.
+    // Do not re-evaluate our sync source if it was set via the replSetSyncFrom command or the
+    // forceSyncSourceCandidate failpoint.
     auto sfp = forceSyncSourceCandidate.scoped();
-    if (_replSetSyncFromSet || MONGO_unlikely(sfp.isActive()) ||
-        !repl::unsupportedSyncSource.empty()) {
+    if (_replSetSyncFromSet || MONGO_unlikely(sfp.isActive())) {
         return false;
     }
 
@@ -3543,7 +3485,7 @@ void TopologyCoordinator::processReplSetRequestVotes(const ReplSetRequestVotesAr
             if (!args.isADryRun()) {
                 _lastVote.setTerm(args.getTerm());
                 _lastVote.setCandidateIndex(args.getCandidateIndex());
-                LOGV2_DEBUG(5972100, 1, "Voting yes in election");
+                LOGV2_DEBUG(5972100, 0, "Voting yes in election");
             }
             response->setVoteGranted(true);
         }