diff --git a/src/test/peerfinder/PeerFinder_test.cpp b/src/test/peerfinder/PeerFinder_test.cpp
index b0750e689f3..5d376e834e6 100644
--- a/src/test/peerfinder/PeerFinder_test.cpp
+++ b/src/test/peerfinder/PeerFinder_test.cpp
@@ -24,6 +24,7 @@
 #include <ripple/peerfinder/impl/Logic.h>
 #include <ripple/protocol/PublicKey.h>
 #include <ripple/protocol/SecretKey.h>
+#include "ripple/beast/unit_test/suite.hpp"
 #include <test/unit_test/SuiteJournal.h>
 
 namespace ripple {
@@ -157,6 +158,108 @@ class PeerFinder_test : public beast::unit_test::suite
         BEAST_EXPECT(n <= (seconds + 59) / 60);
     }
 
+    void
+    test_duplicateOutIn()
+    {
+        auto const seconds = 10000;
+        testcase("duplicate out/in");
+        TestStore store;
+        TestChecker checker;
+        TestStopwatch clock;
+        Logic<TestChecker> logic(clock, store, checker, journal_);
+        logic.addFixedPeer(
+            "test", beast::IP::Endpoint::from_string("65.0.0.1:5"));
+        {
+            Config c;
+            c.autoConnect = false;
+            c.listeningPort = 1024;
+            c.ipLimit = 2;
+            logic.config(c);
+        }
+
+        PublicKey const pk(randomKeyPair(KeyType::secp256k1).first);
+        std::size_t n = 0;
+
+        for (std::size_t i = 0; i < seconds; ++i)
+        {
+            auto const list = logic.autoconnect();
+            if (!list.empty())
+            {
+                BEAST_EXPECT(list.size() == 1);
+                auto const remote = list.front();
+                auto const slot1 = logic.new_outbound_slot(remote);
+                if (BEAST_EXPECT(slot1 != nullptr))
+                {
+                    BEAST_EXPECT(
+                        logic.connectedAddresses_.count(remote.address()) == 1);
+                    auto const local =
+                        beast::IP::Endpoint::from_string("65.0.0.2:1024");
+                    auto const slot2 = logic.new_inbound_slot(local, remote);
+                    BEAST_EXPECT(
+                        logic.connectedAddresses_.count(remote.address()) == 1);
+                    if (!BEAST_EXPECT(slot2 == nullptr))
+                        logic.on_closed(slot2);
+                    logic.on_closed(slot1);
+                }
+                ++n;
+            }
+            clock.advance(std::chrono::seconds(1));
+            logic.once_per_second();
+        }
+        BEAST_EXPECT(n <= (seconds + 59) / 60);
+    }
+
+    void
+    test_duplicateInOut()
+    {
+        auto const seconds = 10000;
+        testcase("duplicate in/out");
+        TestStore store;
+        TestChecker checker;
+        TestStopwatch clock;
+        Logic<TestChecker> logic(clock, store, checker, journal_);
+        logic.addFixedPeer(
+            "test", beast::IP::Endpoint::from_string("65.0.0.1:5"));
+        {
+            Config c;
+            c.autoConnect = false;
+            c.listeningPort = 1024;
+            c.ipLimit = 2;
+            logic.config(c);
+        }
+
+        PublicKey const pk(randomKeyPair(KeyType::secp256k1).first);
+        std::size_t n = 0;
+
+        for (std::size_t i = 0; i < seconds; ++i)
+        {
+            auto const list = logic.autoconnect();
+            if (!list.empty())
+            {
+                BEAST_EXPECT(list.size() == 1);
+                auto const remote = list.front();
+                auto const local =
+                    beast::IP::Endpoint::from_string("65.0.0.2:1024");
+                auto const slot1 = logic.new_inbound_slot(local, remote);
+                if (BEAST_EXPECT(slot1 != nullptr))
+                {
+                    BEAST_EXPECT(
+                        logic.connectedAddresses_.count(remote.address()) == 1);
+                    auto const slot2 = logic.new_outbound_slot(remote);
+                    BEAST_EXPECT(
+                        logic.connectedAddresses_.count(remote.address()) == 1);
+                    if (!BEAST_EXPECT(slot2 == nullptr))
+                        logic.on_closed(slot2);
+                    logic.on_closed(slot1);
+                }
+                ++n;
+            }
+            clock.advance(std::chrono::seconds(1));
+            logic.once_per_second();
+        }
+        BEAST_EXPECT(n <= (seconds + 59) / 60);
+    }
+
     void
     test_config()
     {
@@ -279,6 +382,8 @@ class PeerFinder_test : public beast::unit_test::suite
     {
         test_backoff1();
         test_backoff2();
+        test_duplicateOutIn();
+        test_duplicateInOut();
         test_config();
         test_invalid_config();
     }