SERVER-22007 Disable last-error tracking for help commands.

(cherry picked from commit 8ae053a4d9c5bd2672140964e7f09bd6b734dbdc)

2 files changed, 4 insertions, 1 deletions

diff --git a/src/mongo/db/commands/get_last_error.cpp b/src/mongo/db/commands/get_last_error.cpp
index dfb8a6d7097..e14e13d4221 100644
--- a/src/mongo/db/commands/get_last_error.cpp
+++ b/src/mongo/db/commands/get_last_error.cpp
@@ -93,7 +93,6 @@ public:
                                        const BSONObj& cmdObj,
                                        std::vector<Privilege>* out) {}  // No auth required
     virtual void help(stringstream& help) const {
-        LastError::get(cc()).disable();  // SERVER-11492
         help << "return error status of the last operation on this connection\n"
              << "options:\n"
              << "  { fsync:true } - fsync before returning, or wait for journal commit if running "
diff --git a/src/mongo/db/dbcommands.cpp b/src/mongo/db/dbcommands.cpp
index 2edf13c149e..cf44a4e145e 100644
--- a/src/mongo/db/dbcommands.cpp
+++ b/src/mongo/db/dbcommands.cpp
@@ -1216,6 +1216,10 @@ void Command::execCommand(OperationContext* txn,
 
         if (isHelpRequest(extractedFields[kHelpField])) {
             CurOp::get(txn)->ensureStarted();
+            // We disable last-error for help requests due to SERVER-11492, because config servers
+            // use help requests to determine which commands are database writes, and so must be
+            // forwarded to all mirrored (SCCC) config servers.
+            LastError::get(txn->getClient()).disable();
             generateHelpResponse(txn, request, replyBuilder, *command);
             return;
         }