Prefer replacing dead nodes with the same IP. (#1098)

* Prefer replacing dead nodes with the same IP. * Use reduce to clarify token acquisition logic in the existing token case.
Netflix · Jun 7, 2024 · 479ae9e · 479ae9e
1 parent e93d85e
commit 479ae9e
Show file tree

Hide file tree

Showing 2 changed files with 29 additions and 1 deletion.
diff --git a/priam/src/main/java/com/netflix/priam/identity/token/TokenRetriever.java b/priam/src/main/java/com/netflix/priam/identity/token/TokenRetriever.java
@@ -136,7 +136,16 @@ public PriamInstance retriableCall() throws Exception {
                                 .filter(i -> !racInstanceIds.contains(i.getInstanceId()))
                                 .collect(Collectors.toList());
                 Optional<PriamInstance> candidate =
-                        instances.stream().filter(i -> !isNew(i)).findFirst();
+                        instances
+                                .stream()
+                                .filter(i -> !isNew(i))
+                                .reduce(
+                                        (current, next) ->
+                                                myInstanceInfo
+                                                                .getPrivateIP()
+                                                                .equals(next.getHostIP())
+                                                        ? next
+                                                        : current);
                 candidate.ifPresent(i -> replacedIp = getReplacedIpForExistingToken(allIds, i));
                 if (replacedIp == null) {
                     candidate = instances.stream().filter(i -> isNew(i)).findFirst();

diff --git a/priam/src/test/java/com/netflix/priam/identity/token/TokenRetrieverTest.java b/priam/src/test/java/com/netflix/priam/identity/token/TokenRetrieverTest.java
@@ -169,6 +169,25 @@ public void testReplacementGossipMatch(@Mocked SystemUtils systemUtils) throws E
         Truth.assertThat(tokenRetriever.getReplacedIp().get()).isEqualTo("127.0.0.3");
     }
 
+    @Test
+    public void testPrioritizeDeadTokensWithSameIP(@Mocked SystemUtils systemUtils)
+            throws Exception {
+        create(0, "iid_1", "host_0", "127.0.0.1", instanceInfo.getRac(), 0 + "");
+        create(1, "iid_2", "host_1", "127.1.1.0", instanceInfo.getRac(), 1 + "");
+        new Expectations() {
+            {
+                membership.getRacMembership();
+                result = ImmutableSet.of();
+                SystemUtils.getDataFromUrl(anyString);
+                returns(null, null);
+            }
+        };
+        TokenRetriever tokenRetriever = getTokenRetriever();
+        Truth.assertThat(tokenRetriever.grabExistingToken().getHostIP()).isEqualTo("127.1.1.0");
+        Truth.assertThat(tokenRetriever.getReplacedIp().isPresent()).isTrue();
+        Truth.assertThat(tokenRetriever.getReplacedIp().get()).isEqualTo("127.1.1.0");
+    }
+
     @Test
     public void testPrioritizeDeadTokens(@Mocked SystemUtils systemUtils) throws Exception {
         create(0, "iid_0", "host_0", "127.0.0.0", instanceInfo.getRac(), 0 + "");