diff --git a/solr/CHANGES.txt b/solr/CHANGES.txt
index 27e4606b26e..fe4f8dcc3eb 100644
--- a/solr/CHANGES.txt
+++ b/solr/CHANGES.txt
@@ -198,6 +198,8 @@ Bug Fixes
   and getCore that could cause a request to attempt to use a core that
   has shut down. (yonik)
 
+* SOLR-4926: Fixed rare replication bug that normally only manifested when 
+  using compound file format. (yonik, Mark Miller)
 
 Optimizations
 ----------------------
diff --git a/solr/core/src/java/org/apache/solr/handler/SnapPuller.java b/solr/core/src/java/org/apache/solr/handler/SnapPuller.java
index 2717473504a..cc4259bdb3f 100644
--- a/solr/core/src/java/org/apache/solr/handler/SnapPuller.java
+++ b/solr/core/src/java/org/apache/solr/handler/SnapPuller.java
@@ -403,7 +403,14 @@ public class SnapPuller {
             successfulInstall = modifyIndexProps(tmpIdxDirName);
             deleteTmpIdxDir  =  false;
           } else {
-            successfulInstall = moveIndexFiles(tmpIndexDir, indexDir);
+            solrCore.getUpdateHandler().getSolrCoreState()
+                .closeIndexWriter(core, true);
+            try {
+              successfulInstall = moveIndexFiles(tmpIndexDir, indexDir);
+            } finally {
+              solrCore.getUpdateHandler().getSolrCoreState()
+                  .openIndexWriter(core);
+            }
           }
           if (successfulInstall) {
             if (isFullCopyNeeded) {
@@ -426,7 +433,12 @@ public class SnapPuller {
             successfulInstall = modifyIndexProps(tmpIdxDirName);
             deleteTmpIdxDir =  false;
           } else {
-            successfulInstall = moveIndexFiles(tmpIndexDir, indexDir);
+            solrCore.getUpdateHandler().getSolrCoreState().closeIndexWriter(core, true);
+            try {
+              successfulInstall = moveIndexFiles(tmpIndexDir, indexDir);
+            } finally {
+              solrCore.getUpdateHandler().getSolrCoreState().openIndexWriter(core);
+            }
           }
           if (successfulInstall) {
             logReplicationTimeAndConfFiles(modifiedConfFiles, successfulInstall);
@@ -443,7 +455,11 @@ public class SnapPuller {
               core.getDirectoryFactory().remove(indexDir);
             }
           }
-          openNewWriterAndSearcher(isFullCopyNeeded);
+          if (isFullCopyNeeded) {
+            solrCore.getUpdateHandler().newIndexWriter(isFullCopyNeeded);
+          }
+          
+          openNewSearcherAndUpdateCommitPoint(isFullCopyNeeded);
         }
         
         replicationStartTime = 0;
@@ -615,11 +631,9 @@ public class SnapPuller {
     return sb;
   }
 
-  private void openNewWriterAndSearcher(boolean isFullCopyNeeded) throws IOException {
+  private void openNewSearcherAndUpdateCommitPoint(boolean isFullCopyNeeded) throws IOException {
     SolrQueryRequest req = new LocalSolrQueryRequest(solrCore,
         new ModifiableSolrParams());
-    // reboot the writer on the new index and get a new searcher
-    solrCore.getUpdateHandler().newIndexWriter(isFullCopyNeeded);
     
     RefCounted<SolrIndexSearcher> searcher = null;
     IndexCommit commitPoint;
diff --git a/solr/core/src/java/org/apache/solr/update/DefaultSolrCoreState.java b/solr/core/src/java/org/apache/solr/update/DefaultSolrCoreState.java
index 2b345442179..ef0a2a98287 100644
--- a/solr/core/src/java/org/apache/solr/update/DefaultSolrCoreState.java
+++ b/solr/core/src/java/org/apache/solr/update/DefaultSolrCoreState.java
@@ -187,6 +187,76 @@ public final class DefaultSolrCoreState extends SolrCoreState implements Recover
       }
     }
   }
+  
+  @Override
+  public synchronized void closeIndexWriter(SolrCore core, boolean rollback)
+      throws IOException {
+    log.info("Closing IndexWriter...");
+    String coreName = core.getName();
+    synchronized (writerPauseLock) {
+      if (closed) {
+        throw new SolrException(ErrorCode.SERVICE_UNAVAILABLE, "Already closed");
+      }
+      
+      // we need to wait for the Writer to fall out of use
+      // first lets stop it from being lent out
+      pauseWriter = true;
+      // then lets wait until its out of use
+      log.info("Waiting until IndexWriter is unused... core=" + coreName);
+      
+      while (!writerFree) {
+        try {
+          writerPauseLock.wait(100);
+        } catch (InterruptedException e) {}
+        
+        if (closed) {
+          throw new SolrException(ErrorCode.SERVICE_UNAVAILABLE,
+              "SolrCoreState already closed");
+        }
+      }
+      
+      if (indexWriter != null) {
+        if (!rollback) {
+          try {
+            log.info("Closing old IndexWriter... core=" + coreName);
+            indexWriter.close();
+          } catch (Throwable t) {
+            SolrException.log(log, "Error closing old IndexWriter. core="
+                + coreName, t);
+          }
+        } else {
+          try {
+            log.info("Rollback old IndexWriter... core=" + coreName);
+            indexWriter.rollback();
+          } catch (Throwable t) {
+            SolrException.log(log, "Error rolling back old IndexWriter. core="
+                + coreName, t);
+          }
+        }
+      }
+      
+    }
+  }
+  
+  @Override
+  public synchronized void openIndexWriter(SolrCore core) throws IOException {
+    log.info("Creating new IndexWriter...");
+    synchronized (writerPauseLock) {
+      if (closed) {
+        throw new SolrException(ErrorCode.SERVICE_UNAVAILABLE, "Already closed");
+      }
+      
+      try {
+        indexWriter = createMainIndexWriter(core, "DirectUpdateHandler2");
+        log.info("New IndexWriter is ready to be used.");
+        // we need to null this so it picks up the new writer next get call
+        refCntWriter = null;
+      } finally {
+        pauseWriter = false;
+        writerPauseLock.notifyAll();
+      }
+    }
+  }
 
   @Override
   public synchronized void rollbackIndexWriter(SolrCore core) throws IOException {
diff --git a/solr/core/src/java/org/apache/solr/update/SolrCoreState.java b/solr/core/src/java/org/apache/solr/update/SolrCoreState.java
index cad8671e7b1..5464d2894a4 100644
--- a/solr/core/src/java/org/apache/solr/update/SolrCoreState.java
+++ b/solr/core/src/java/org/apache/solr/update/SolrCoreState.java
@@ -88,6 +88,26 @@ public abstract class SolrCoreState {
    */
   public abstract void newIndexWriter(SolrCore core, boolean rollback) throws IOException;
   
+  
+  /**
+   * Expert method that closes the IndexWriter - you must call {@link #openIndexWriter(SolrCore)}
+   * in a finally block after calling this method.
+   * 
+   * @param core that the IW belongs to
+   * @param rollback true if IW should rollback rather than close
+   * @throws IOException If there is a low-level I/O error.
+   */
+  public abstract void closeIndexWriter(SolrCore core, boolean rollback) throws IOException;
+  
+  /**
+   * Expert method that opens the IndexWriter - you must call {@link #closeIndexWriter(SolrCore, boolean)}
+   * first, and then call this method in a finally block.
+   * 
+   * @param core that the IW belongs to
+   * @throws IOException If there is a low-level I/O error.
+   */
+  public abstract void openIndexWriter(SolrCore core) throws IOException;
+  
   /**
    * Get the current IndexWriter. If a new IndexWriter must be created, use the
    * settings from the given {@link SolrCore}.