apache · psalagnac · Dec 29, 2025 · Dec 18, 2025 · Dec 29, 2025 · Dec 29, 2025
diff --git a/changelog/unreleased/SOLR-16116-remove-retryOnConnLoss.yml b/changelog/unreleased/SOLR-16116-remove-retryOnConnLoss.yml
@@ -0,0 +1,8 @@
+title: Remove parameter retryOnConnLoss everywhere from the codebase. This parameter
+  was already fully ignored since the move to Curator.
+type: removed
+authors:
+  - name: Pierre Salagnac
+links:
+  - name: SOLR-16116
+    url: https://issues.apache.org/jira/browse/SOLR-16116
diff --git a/solr/core/src/java/org/apache/solr/api/ZkClusterPluginsSource.java b/solr/core/src/java/org/apache/solr/api/ZkClusterPluginsSource.java
@@ -71,7 +71,7 @@ public Map<String, Object> plugins() throws IOException {
     try {
       Map<String, Object> clusterPropsJson =
           (Map<String, Object>)
-              Utils.fromJSON(zkClient.getData(ZkStateReader.CLUSTER_PROPS, null, new Stat(), true));
+              Utils.fromJSON(zkClient.getData(ZkStateReader.CLUSTER_PROPS, null, new Stat()));
       return Map.copyOf(
           (Map<String, Object>)
               clusterPropsJson.computeIfAbsent(

diff --git a/solr/core/src/java/org/apache/solr/cli/AuthTool.java b/solr/core/src/java/org/apache/solr/cli/AuthTool.java
@@ -249,7 +249,7 @@ private void handleBasicAuth(CommandLine cli) throws Exception {
         if (!updateIncludeFileOnly) {
           echoIfVerbose("Uploading following security.json: " + securityJson);
           try (SolrZkClient zkClient = CLIUtils.getSolrZkClient(cli, zkHost)) {
-            zkClient.setData("/security.json", securityJson.getBytes(StandardCharsets.UTF_8), true);
+            zkClient.setData("/security.json", securityJson.getBytes(StandardCharsets.UTF_8));
           }
         }
 
@@ -309,8 +309,8 @@ private void handleBasicAuth(CommandLine cli) throws Exception {
 
   private void checkSecurityJsonExists(SolrZkClient zkClient)
       throws KeeperException, InterruptedException {
-    if (zkClient.exists("/security.json", true)) {
-      byte[] oldSecurityBytes = zkClient.getData("/security.json", null, null, true);
+    if (zkClient.exists("/security.json")) {
+      byte[] oldSecurityBytes = zkClient.getData("/security.json", null, null);
       if (!"{}".equals(new String(oldSecurityBytes, StandardCharsets.UTF_8).trim())) {
         CLIO.out(
             "Security is already enabled. You can disable it with 'bin/solr auth disable'. Existing security.json: \n"
@@ -332,7 +332,7 @@ private void clearSecurityJson(CommandLine cli, boolean updateIncludeFileOnly) t
       echoIfVerbose("Uploading following security.json: {}");
 
       try (SolrZkClient zkClient = CLIUtils.getSolrZkClient(cli, zkHost)) {
-        zkClient.setData("/security.json", "{}".getBytes(StandardCharsets.UTF_8), true);
+        zkClient.setData("/security.json", "{}".getBytes(StandardCharsets.UTF_8));
       }
     }
   }

diff --git a/solr/core/src/java/org/apache/solr/cli/CreateTool.java b/solr/core/src/java/org/apache/solr/cli/CreateTool.java
@@ -248,9 +248,7 @@ protected void createCollection(CloudSolrClient cloudSolrClient, CommandLine cli
     boolean configExistsInZk =
         confName != null
             && !confName.trim().isEmpty()
-            && ZkStateReader.from(cloudSolrClient)
-                .getZkClient()
-                .exists("/configs/" + confName, true);
+            && ZkStateReader.from(cloudSolrClient).getZkClient().exists("/configs/" + confName);
 
     if (configExistsInZk) {
       echo("Re-using existing configuration directory " + confName);

diff --git a/solr/core/src/java/org/apache/solr/cli/ZkMkrootTool.java b/solr/core/src/java/org/apache/solr/cli/ZkMkrootTool.java
@@ -79,7 +79,7 @@ public void runImpl(CommandLine cli) throws Exception {
       echoIfVerbose("\nConnecting to ZooKeeper at " + zkHost + " ...");
 
       echo("Creating ZooKeeper path " + znode + " on ZooKeeper at " + zkHost);
-      zkClient.makePath(znode, failOnExists, true);
+      zkClient.makePath(znode, failOnExists);
     } catch (Exception e) {
       log.error("Could not complete mkroot operation for reason: ", e);
       throw (e);

diff --git a/solr/core/src/java/org/apache/solr/cli/ZkRmTool.java b/solr/core/src/java/org/apache/solr/cli/ZkRmTool.java
@@ -67,7 +67,7 @@ public void runImpl(CommandLine cli) throws Exception {
     }
     echoIfVerbose("\nConnecting to ZooKeeper at " + zkHost + " ...");
     try (SolrZkClient zkClient = CLIUtils.getSolrZkClient(cli, zkHost)) {
-      if (!recursive && zkClient.getChildren(znode, null, true).size() != 0) {
+      if (!recursive && zkClient.getChildren(znode, null).size() != 0) {
         throw new SolrServerException(
             "ZooKeeper node " + znode + " has children and recursive has NOT been specified.");
       }

diff --git a/solr/core/src/java/org/apache/solr/cloud/CloudUtil.java b/solr/core/src/java/org/apache/solr/cloud/CloudUtil.java
@@ -129,10 +129,10 @@ public static String unifiedResourcePath(SolrResourceLoader loader) {
   public static Map<String, byte[]> getTrustedKeys(SolrZkClient zk, String dir) {
     Map<String, byte[]> result = new HashMap<>();
     try {
-      List<String> children = zk.getChildren("/keys/" + dir, null, true);
+      List<String> children = zk.getChildren("/keys/" + dir, null);
       for (String key : children) {
         if (key.endsWith(".der"))
-          result.put(key, zk.getData("/keys/" + dir + "/" + key, null, null, true));
+          result.put(key, zk.getData("/keys/" + dir + "/" + key, null, null));
       }
     } catch (KeeperException.NoNodeException e) {
       log.info("Error fetching key names");

diff --git a/solr/core/src/java/org/apache/solr/cloud/DistributedApiAsyncTracker.java b/solr/core/src/java/org/apache/solr/cloud/DistributedApiAsyncTracker.java
@@ -323,8 +323,8 @@ enum State {
       this.rootNodePath = rootNodePath;
 
       try {
-        if (!zkClient.exists(rootNodePath, true)) {
-          zkClient.makePath(rootNodePath, new byte[0], CreateMode.PERSISTENT, true);
+        if (!zkClient.exists(rootNodePath)) {
+          zkClient.makePath(rootNodePath, new byte[0], CreateMode.PERSISTENT);
         }
       } catch (KeeperException.NodeExistsException nee) {
         // Some other thread (on this or another JVM) beat us to create the node, that's ok, the
@@ -341,27 +341,25 @@ void createNewInFlightTask(String asyncId) throws KeeperException, InterruptedEx
       zkClient.create(
           getPath(asyncId),
           State.SUBMITTED.shorthand.getBytes(StandardCharsets.UTF_8),
-          CreateMode.EPHEMERAL,
-          true);
+          CreateMode.EPHEMERAL);
     }
 
     void setTaskRunning(String asyncId) throws KeeperException, InterruptedException {
-      zkClient.setData(
-          getPath(asyncId), State.RUNNING.shorthand.getBytes(StandardCharsets.UTF_8), true);
+      zkClient.setData(getPath(asyncId), State.RUNNING.shorthand.getBytes(StandardCharsets.UTF_8));
     }
 
     void deleteInFlightTask(String asyncId) throws KeeperException, InterruptedException {
-      zkClient.delete(getPath(asyncId), -1, true);
+      zkClient.delete(getPath(asyncId), -1);
     }
 
     State getInFlightState(String asyncId) throws KeeperException, InterruptedException {
-      if (!zkClient.exists(getPath(asyncId), true)) {
+      if (!zkClient.exists(getPath(asyncId))) {
         return State.NOT_FOUND;
       }
 
       final byte[] bytes;
       try {
-        bytes = zkClient.getData(getPath(asyncId), null, null, true);
+        bytes = zkClient.getData(getPath(asyncId), null, null);
       } catch (KeeperException.NoNodeException nne) {
         // Unlikely race, but not impossible...
         if (log.isInfoEnabled()) {

diff --git a/solr/core/src/java/org/apache/solr/cloud/DistributedClusterStateUpdater.java b/solr/core/src/java/org/apache/solr/cloud/DistributedClusterStateUpdater.java
@@ -552,7 +552,7 @@ private void doStateDotJsonCasUpdate(ClusterState updatedState)
         if (updater.isCollectionCreation()) {
           // The state.json file does not exist yet (more precisely it is assumed not to exist)
           log.debug("going to create collection {}", jsonPath);
-          zkStateReader.getZkClient().create(jsonPath, stateJson, CreateMode.PERSISTENT, true);
+          zkStateReader.getZkClient().create(jsonPath, stateJson, CreateMode.PERSISTENT);
         } else {
           // We're updating an existing state.json
           if (log.isDebugEnabled()) {
@@ -561,9 +561,7 @@ private void doStateDotJsonCasUpdate(ClusterState updatedState)
                 jsonPath,
                 collection.getZNodeVersion());
           }
-          zkStateReader
-              .getZkClient()
-              .setData(jsonPath, stateJson, collection.getZNodeVersion(), true);
+          zkStateReader.getZkClient().setData(jsonPath, stateJson, collection.getZNodeVersion());
         }
       }
     }
@@ -577,7 +575,7 @@ private void doStateDotJsonCasUpdate(ClusterState updatedState)
     private ClusterState fetchStateForCollection() throws KeeperException, InterruptedException {
       String collectionStatePath = DocCollection.getCollectionPath(updater.getCollectionName());
       Stat stat = new Stat();
-      byte[] data = zkStateReader.getZkClient().getData(collectionStatePath, null, stat, true);
+      byte[] data = zkStateReader.getZkClient().getData(collectionStatePath, null, stat);
 
       // This factory method can detect a missing configName and supply it by reading it from the
       // old ZK location.
@@ -890,7 +888,7 @@ public static void executeNodeDownStateUpdate(String nodeName, ZkStateReader zkS
 
       try {
         final List<String> collectionNames =
-            zkStateReader.getZkClient().getChildren(COLLECTIONS_ZKNODE, null, true);
+            zkStateReader.getZkClient().getChildren(COLLECTIONS_ZKNODE, null);
 
         // Collections are totally independent of each other. Multiple threads could share the load
         // here (need a ZK connection for each though).

diff --git a/solr/core/src/java/org/apache/solr/cloud/DistributedMap.java b/solr/core/src/java/org/apache/solr/cloud/DistributedMap.java
@@ -68,8 +68,7 @@ private void assertKeyFormat(String trackingId) {
 
   public void put(String trackingId, byte[] data) throws KeeperException, InterruptedException {
     assertKeyFormat(trackingId);
-    zookeeper.makePath(
-        dir + "/" + PREFIX + trackingId, data, CreateMode.PERSISTENT, null, false, true);
+    zookeeper.makePath(dir + "/" + PREFIX + trackingId, data, CreateMode.PERSISTENT, null, false);
   }
 
   /**
@@ -81,25 +80,24 @@ public boolean putIfAbsent(String trackingId, byte[] data)
       throws KeeperException, InterruptedException {
     assertKeyFormat(trackingId);
     try {
-      zookeeper.makePath(
-          dir + "/" + PREFIX + trackingId, data, CreateMode.PERSISTENT, null, true, true);
+      zookeeper.makePath(dir + "/" + PREFIX + trackingId, data, CreateMode.PERSISTENT, null, true);
       return true;
     } catch (NodeExistsException e) {
       return false;
     }
   }
 
   public byte[] get(String trackingId) throws KeeperException, InterruptedException {
-    return zookeeper.getData(dir + "/" + PREFIX + trackingId, null, null, true);
+    return zookeeper.getData(dir + "/" + PREFIX + trackingId, null, null);
   }
 
   public boolean contains(String trackingId) throws KeeperException, InterruptedException {
-    return zookeeper.exists(dir + "/" + PREFIX + trackingId, true);
+    return zookeeper.exists(dir + "/" + PREFIX + trackingId);
   }
 
   public int size() throws KeeperException, InterruptedException {
     Stat stat = new Stat();
-    zookeeper.getData(dir, null, stat, true);
+    zookeeper.getData(dir, null, stat);
     return stat.getNumChildren();
   }
 
@@ -110,7 +108,7 @@ public int size() throws KeeperException, InterruptedException {
   public boolean remove(String trackingId) throws KeeperException, InterruptedException {
     final var path = dir + "/" + PREFIX + trackingId;
     try {
-      zookeeper.delete(path, -1, true);
+      zookeeper.delete(path, -1);
     } catch (KeeperException.NoNodeException e) {
       return false;
     } catch (KeeperException.NotEmptyException hack) {
@@ -123,15 +121,15 @@ public boolean remove(String trackingId) throws KeeperException, InterruptedExce
 
   /** Helper method to clear all child nodes for a parent node. */
   public void clear() throws KeeperException, InterruptedException {
-    List<String> childNames = zookeeper.getChildren(dir, null, true);
+    List<String> childNames = zookeeper.getChildren(dir, null);
     for (String childName : childNames) {
-      zookeeper.delete(dir + "/" + childName, -1, true);
+      zookeeper.delete(dir + "/" + childName, -1);
     }
   }
 
   /** Returns the keys of all the elements in the map */
   public Collection<String> keys() throws KeeperException, InterruptedException {
-    List<String> childs = zookeeper.getChildren(dir, null, true);
+    List<String> childs = zookeeper.getChildren(dir, null);
     final List<String> ids = new ArrayList<>(childs.size());
     childs.stream().forEach((child) -> ids.add(child.substring(PREFIX.length())));
     return ids;

diff --git a/solr/core/src/java/org/apache/solr/cloud/ElectionContext.java b/solr/core/src/java/org/apache/solr/cloud/ElectionContext.java
@@ -55,7 +55,7 @@ public void cancelElection() throws InterruptedException, KeeperException {
     if (leaderSeqPath != null) {
       try {
         log.debug("Canceling election {}", leaderSeqPath);
-        zkClient.delete(leaderSeqPath, -1, true);
+        zkClient.delete(leaderSeqPath, -1);
       } catch (NoNodeException e) {
         // fine
         log.debug("cancelElection did not find election node to remove {}", leaderSeqPath);

diff --git a/solr/core/src/java/org/apache/solr/cloud/LeaderElector.java b/solr/core/src/java/org/apache/solr/cloud/LeaderElector.java
@@ -94,7 +94,7 @@ private void checkIfIamLeader(final ElectionContext context, boolean replacement
     context.checkIfIamLeaderFired();
     // get all other numbers...
     final String holdElectionPath = context.electionPath + ELECTION_NODE;
-    List<String> seqs = zkClient.getChildren(holdElectionPath, null, true);
+    List<String> seqs = zkClient.getChildren(holdElectionPath, null);
     sortSeqs(seqs);
 
     String leaderSeqNodeName =
@@ -114,7 +114,7 @@ private void checkIfIamLeader(final ElectionContext context, boolean replacement
         try {
           String toDelete = holdElectionPath + "/" + elec;
           log.warn("Deleting duplicate registration: {}", toDelete);
-          zkClient.delete(toDelete, -1, true);
+          zkClient.delete(toDelete, -1);
         } catch (KeeperException.NoNodeException e) {
           // ignore
         }
@@ -148,8 +148,7 @@ private void checkIfIamLeader(final ElectionContext context, boolean replacement
             watcher =
                 new ElectionWatcher(
                     context.leaderSeqPath, watchedNode, getSeq(context.leaderSeqPath), context),
-            null,
-            true);
+            null);
         log.debug("Watching path {} to know if I could be the leader", watchedNode);
       } catch (KeeperException.SessionExpiredException e) {
         throw e;
@@ -240,10 +239,7 @@ public int joinElection(ElectionContext context, boolean replacement, boolean jo
           if (nodes.size() < 2) {
             leaderSeqPath =
                 zkClient.create(
-                    shardsElectZkPath + "/" + id + "-n_",
-                    null,
-                    CreateMode.EPHEMERAL_SEQUENTIAL,
-                    false);
+                    shardsElectZkPath + "/" + id + "-n_", null, CreateMode.EPHEMERAL_SEQUENTIAL);
           } else {
             String firstInLine = nodes.get(1);
             log.debug("The current head: {}", firstInLine);
@@ -252,23 +248,20 @@ public int joinElection(ElectionContext context, boolean replacement, boolean jo
               throw new IllegalStateException("Could not find regex match in:" + firstInLine);
             }
             leaderSeqPath = shardsElectZkPath + "/" + id + "-n_" + m.group(1);
-            zkClient.create(leaderSeqPath, null, CreateMode.EPHEMERAL, false);
+            zkClient.create(leaderSeqPath, null, CreateMode.EPHEMERAL);
           }
         } else {
           leaderSeqPath =
               zkClient.create(
-                  shardsElectZkPath + "/" + id + "-n_",
-                  null,
-                  CreateMode.EPHEMERAL_SEQUENTIAL,
-                  false);
+                  shardsElectZkPath + "/" + id + "-n_", null, CreateMode.EPHEMERAL_SEQUENTIAL);
         }
 
         log.debug("Joined leadership election with path: {}", leaderSeqPath);
         context.leaderSeqPath = leaderSeqPath;
         cont = false;
       } catch (ConnectionLossException e) {
         // we don't know if we made our node or not...
-        List<String> entries = zkClient.getChildren(shardsElectZkPath, null, true);
+        List<String> entries = zkClient.getChildren(shardsElectZkPath, null);
 
         boolean foundId = false;
         for (String entry : entries) {
@@ -336,7 +329,7 @@ public void process(WatchedEvent event) {
       if (canceled) {
         log.debug("This watcher is not active anymore {}", myNode);
         try {
-          zkClient.delete(myNode, -1, true);
+          zkClient.delete(myNode, -1);
         } catch (KeeperException.NoNodeException nne) {
           // expected . don't do anything
         } catch (Exception e) {

diff --git a/solr/core/src/java/org/apache/solr/cloud/Overseer.java b/solr/core/src/java/org/apache/solr/cloud/Overseer.java
@@ -465,7 +465,7 @@ private void checkIfIamStillLeader() {
       final String path = OVERSEER_ELECT + "/leader";
       byte[] data;
       try {
-        data = zkClient.getData(path, null, stat, true);
+        data = zkClient.getData(path, null, stat);
       } catch (IllegalStateException | KeeperException.NoNodeException e) {
         return;
       } catch (Exception e) {
@@ -480,7 +480,7 @@ private void checkIfIamStillLeader() {
             log.warn(
                 "I (id={}) am exiting, but I'm still the leader",
                 overseerCollectionConfigSetProcessor.getId());
-            zkClient.delete(path, stat.getVersion(), true);
+            zkClient.delete(path, stat.getVersion());
           } catch (KeeperException.BadVersionException e) {
             // no problem ignore it some other Overseer has already taken over
           } catch (Exception e) {
@@ -602,7 +602,7 @@ private LeaderStatus amILeader() {
       String propsId = null;
       try {
         ZkNodeProps props =
-            ZkNodeProps.load(zkClient.getData(OVERSEER_ELECT + "/leader", null, null, true));
+            ZkNodeProps.load(zkClient.getData(OVERSEER_ELECT + "/leader", null, null));
         propsId = props.getStr(ID);
         if (myId.equals(propsId)) {
           return LeaderStatus.YES;
@@ -1027,7 +1027,7 @@ OverseerTaskQueue getConfigSetQueue(final SolrZkClient zkClient, Stats zkStats)
 
   private void createOverseerNode(final SolrZkClient zkClient) {
     try {
-      zkClient.create("/overseer", new byte[0], CreateMode.PERSISTENT, true);
+      zkClient.create("/overseer", new byte[0], CreateMode.PERSISTENT);
     } catch (KeeperException.NodeExistsException e) {
       // ok
     } catch (InterruptedException e) {

diff --git a/solr/core/src/java/org/apache/solr/cloud/OverseerElectionContext.java b/solr/core/src/java/org/apache/solr/cloud/OverseerElectionContext.java
@@ -62,7 +62,7 @@ void runLeaderProcess(boolean weAreReplacement, int pauseBeforeStartMs)
     final String id = leaderSeqPath.substring(leaderSeqPath.lastIndexOf('/') + 1);
     ZkNodeProps myProps = new ZkNodeProps(ID, id);
 
-    zkClient.makePath(leaderPath, Utils.toJSON(myProps), CreateMode.EPHEMERAL, true);
+    zkClient.makePath(leaderPath, Utils.toJSON(myProps), CreateMode.EPHEMERAL);
     if (pauseBeforeStartMs > 0) {
       try {
         Thread.sleep(pauseBeforeStartMs);

diff --git a/solr/core/src/java/org/apache/solr/cloud/OverseerNodePrioritizer.java b/solr/core/src/java/org/apache/solr/cloud/OverseerNodePrioritizer.java
@@ -67,9 +67,8 @@ public OverseerNodePrioritizer(
   public synchronized void prioritizeOverseerNodes(String overseerId) throws Exception {
     SolrZkClient zk = zkStateReader.getZkClient();
     List<String> overseerDesignates = new ArrayList<>();
-    if (zk.exists(ZkStateReader.ROLES, true)) {
-      Map<?, ?> m =
-          (Map<?, ?>) Utils.fromJSON(zk.getData(ZkStateReader.ROLES, null, new Stat(), true));
+    if (zk.exists(ZkStateReader.ROLES)) {
+      Map<?, ?> m = (Map<?, ?>) Utils.fromJSON(zk.getData(ZkStateReader.ROLES, null, new Stat()));
       @SuppressWarnings("unchecked")
       List<String> l = (List<String>) m.get("overseer");
       if (l != null) {