diff --git a/cnc/src/main/java/org/btcollider/cnc/keysrv/KeyServer.java b/cnc/src/main/java/org/btcollider/cnc/keysrv/KeyServer.java
index ad79762..fd02fdf 100644
--- a/cnc/src/main/java/org/btcollider/cnc/keysrv/KeyServer.java
+++ b/cnc/src/main/java/org/btcollider/cnc/keysrv/KeyServer.java
@@ -1,6 +1,8 @@
 package org.btcollider.cnc.keysrv;
 
-import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
 import org.btcollider.cnc.dto.KeyRange;
 
 public interface KeyServer {
@@ -34,9 +36,20 @@ public interface KeyServer {
    * Dumps the state of the keys managed by this KeyServer to a file. A KeyServer must be able to
    * read back the status of its keys from its dump file, but not necessarily from other KeyServers.
    *
-   * @param file The file to dump the key state to. Path must exist and must be write-able. Not
-   *        null.
+   * @param out The output stream to write the dump to. Not null.
    */
-  void dump(File file);
+  void dump(OutputStream out) throws IOException;
+
+  /**
+   * Recreates the keys of a KeyServer from a dump. A KeyServer must be able to read back the status
+   * of its keys form a dump file, but not necessarily from other KeyServers.
+   *
+   * Use this method only directly after initialization on a fresh KeyServer. Otherwise the state
+   * might be unexpected.
+   *
+   * @param int The input stream to read the dump from. Not null.
+   * @throws IOException The undumping failed. Keys are in an undefined state.
+   */
+  void undump(InputStream in) throws IOException;
 
 }
diff --git a/cnc/src/main/java/org/btcollider/cnc/keysrv/keytree/KeyTreeServer.java b/cnc/src/main/java/org/btcollider/cnc/keysrv/keytree/KeyTreeServer.java
index 5c6ce1d..10b6961 100644
--- a/cnc/src/main/java/org/btcollider/cnc/keysrv/keytree/KeyTreeServer.java
+++ b/cnc/src/main/java/org/btcollider/cnc/keysrv/keytree/KeyTreeServer.java
@@ -1,6 +1,8 @@
 package org.btcollider.cnc.keysrv.keytree;
 
-import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
 import java.util.BitSet;
 import java.util.LinkedList;
 import java.util.Queue;
@@ -307,7 +309,48 @@ public class KeyTreeServer implements KeyServer {
   }
 
   @Override
-  public void dump(File file) {
+  public void dump(OutputStream out) throws IOException {
+    // Dump the KeyTree depth first
+    synchronized (this) {
+      recDump(root, out);
+    }
+  }
 
+  private void recDump(KeyTree node, OutputStream out) throws IOException {
+    if (node == null)
+      return;
+
+    int dumpByte = (node.getValue() ? 0b01 : 0b00) | (node.isSearched() ? 0b10 : 0b00);
+
+    out.write(dumpByte);
+
+    recDump(node.getLeft(), out);
+    recDump(node.getRight(), out);
+  }
+
+  @Override
+  public void undump(InputStream in) throws IOException {
+    // Read dump depth first
+    synchronized (this) {
+      recUndump(root, in);
+    }
+  }
+
+  private void recUndump(KeyTree node, InputStream in) throws IOException {
+    if (node == null) {
+      assert (in.read() == -1);
+      return;
+    }
+
+    int dumpByte = in.read();
+    int value = dumpByte & 0b01;
+    int searched = dumpByte & 0b10;
+
+    assert ((value == 0 && !node.getValue()) || (value == 1 && node.getValue()));
+
+    node.setSearched(searched == 0 ? false : true);
+
+    recUndump(node.getLeft(), in);
+    recUndump(node.getRight(), in);
   }
 }
diff --git a/cnc/src/main/java/org/btcollider/cnc/keysrv/multistage/KeyRangeBuffer.java b/cnc/src/main/java/org/btcollider/cnc/keysrv/multistage/KeyRangeBuffer.java
index c7fccee..44f5914 100644
--- a/cnc/src/main/java/org/btcollider/cnc/keysrv/multistage/KeyRangeBuffer.java
+++ b/cnc/src/main/java/org/btcollider/cnc/keysrv/multistage/KeyRangeBuffer.java
@@ -2,6 +2,7 @@ package org.btcollider.cnc.keysrv.multistage;
 
 import java.util.HashMap;
 import java.util.Map.Entry;
+import java.util.Set;
 import org.btcollider.cnc.dto.KeyRange;
 
 /**
@@ -45,4 +46,8 @@ public class KeyRangeBuffer {
 
     return retracedRange;
   }
+
+  protected Set<KeyRange> getAllRanges() {
+    return keyRanges.keySet();
+  }
 }
diff --git a/cnc/src/main/java/org/btcollider/cnc/keysrv/multistage/MultiStagedServer.java b/cnc/src/main/java/org/btcollider/cnc/keysrv/multistage/MultiStagedServer.java
index 14f7140..4271e9c 100644
--- a/cnc/src/main/java/org/btcollider/cnc/keysrv/multistage/MultiStagedServer.java
+++ b/cnc/src/main/java/org/btcollider/cnc/keysrv/multistage/MultiStagedServer.java
@@ -1,6 +1,15 @@
 package org.btcollider.cnc.keysrv.multistage;
 
-import java.io.File;
+import java.io.BufferedReader;
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.OutputStream;
+import java.io.OutputStreamWriter;
+import java.io.PrintWriter;
+import java.nio.charset.StandardCharsets;
 import org.btcollider.cnc.dto.KeyRange;
 import org.btcollider.cnc.keysrv.KeyServer;
 import org.btcollider.cnc.keysrv.keytree.KeyTreeServer;
@@ -16,7 +25,7 @@ import org.slf4j.LoggerFactory;
  */
 public class MultiStagedServer implements KeyServer {
   final Logger log = LoggerFactory.getLogger(MultiStagedServer.class);
-  private static final int PARTITION_DEPTH = 15;
+  private static final int PARTITION_DEPTH = 16;
 
   private KeyTreeServer primKTS;
   private KeyTreeServer secKTS;
@@ -108,8 +117,63 @@ public class MultiStagedServer implements KeyServer {
   }
 
   @Override
-  public void dump(File file) {
+  public void dump(OutputStream out) throws IOException {
+    synchronized (this) {
+      ByteArrayOutputStream primDump = new ByteArrayOutputStream();
+      primKTS.dump(primDump);
+      primDump.flush();
 
+      ByteArrayOutputStream secDump = new ByteArrayOutputStream();
+      secKTS.dump(secDump);
+      secDump.flush();
+
+      out.write(primDump.toByteArray());
+      out.write(0xFF);
+      out.write(secDump.toByteArray());
+      out.write(0xFF);
+      out.flush();
+
+      PrintWriter pw = new PrintWriter(new OutputStreamWriter(out, StandardCharsets.US_ASCII));
+      pw.println();
+      pw.println(partition.getStart() + "," + partition.getEnd());
+
+      keyRangeBuffer.getAllRanges().forEach(kr -> pw.println(kr.getStart() + "," + kr.getEnd()));
+      pw.flush();
+
+      out.flush();
+    }
+  }
+
+  @Override
+  public void undump(InputStream in) throws IOException {
+    synchronized (this) {
+      ByteArrayOutputStream bos = new ByteArrayOutputStream();
+      for (int b = in.read(); b != 0xFF; b = in.read()) {
+        bos.write(b);
+      }
+      ByteArrayInputStream bis = new ByteArrayInputStream(bos.toByteArray());
+      primKTS.undump(bis);
+
+      bos = new ByteArrayOutputStream();
+      for (int b = in.read(); b != 0xFF; b = in.read()) {
+        bos.write(b);
+      }
+      bis = new ByteArrayInputStream(bos.toByteArray());
+      secKTS.undump(bis);
+
+      BufferedReader br = new BufferedReader(new InputStreamReader(in, StandardCharsets.US_ASCII));
+      br.readLine();
+      String[] partitionDump = br.readLine().split(",");
+      this.partition =
+          new KeyRange(Long.parseLong(partitionDump[0]), Long.parseLong(partitionDump[1]));
+
+      String krbuf;
+      while ((krbuf = br.readLine()) != null) {
+        String[] krbufsplit = krbuf.split(",");
+        keyRangeBuffer
+            .setInWork(new KeyRange(Long.parseLong(krbufsplit[0]), Long.parseLong(krbufsplit[1])));
+      }
+    }
   }
 
 }