diff --git a/arangod/Cluster/ClusterMethods.cpp b/arangod/Cluster/ClusterMethods.cpp
index 31ca63f30d..2235650412 100644
--- a/arangod/Cluster/ClusterMethods.cpp
+++ b/arangod/Cluster/ClusterMethods.cpp
@@ -53,8 +53,14 @@
 using namespace arangodb::basics;
 using namespace arangodb::rest;
 
+// Timeout for read operations:
 static double const CL_DEFAULT_TIMEOUT = 120.0;
 
+// Timeout for write operations, note that these are used for communication
+// with a shard leader and we always have to assume that some follower has
+// stopped writes for some time to get in sync:
+static double const CL_DEFAULT_LONG_TIMEOUT = 900.0;
+
 namespace {
 template<typename T>
 T addFigures(VPackSlice const& v1, VPackSlice const& v2, std::vector<std::string> const& attr) {
@@ -231,7 +237,12 @@ static void mergeResults(
         arr.get(StaticStrings::Error).isBoolean() && arr.get(StaticStrings::Error).getBoolean()) {
       // an error occurred, now rethrow the error
       int res = arr.get(StaticStrings::ErrorNum).getNumericValue<int>();
-      THROW_ARANGO_EXCEPTION(res);
+      VPackSlice msg = arr.get(StaticStrings::ErrorMessage);
+      if (msg.isString()) {
+        THROW_ARANGO_EXCEPTION_MESSAGE(res, msg.copyString());
+      } else {
+        THROW_ARANGO_EXCEPTION(res);
+      }
     }
     resultBody->add(arr.at(pair.second));
   }
@@ -1186,7 +1197,7 @@ Result createDocumentOnCoordinator(
 
   // Perform the requests
   size_t nrDone = 0;
-  cc->performRequests(requests, CL_DEFAULT_TIMEOUT, nrDone, Logger::COMMUNICATION, true);
+  cc->performRequests(requests, CL_DEFAULT_LONG_TIMEOUT, nrDone, Logger::COMMUNICATION, true);
 
   // Now listen to the results:
   if (!useMultiple) {
@@ -1350,7 +1361,7 @@ int deleteDocumentOnCoordinator(
 
     // Perform the requests
     size_t nrDone = 0;
-    cc->performRequests(requests, CL_DEFAULT_TIMEOUT, nrDone, Logger::COMMUNICATION, true);
+    cc->performRequests(requests, CL_DEFAULT_LONG_TIMEOUT, nrDone, Logger::COMMUNICATION, true);
 
     // Now listen to the results:
     if (!useMultiple) {
@@ -1400,7 +1411,7 @@ int deleteDocumentOnCoordinator(
 
   // Perform the requests
   size_t nrDone = 0;
-  cc->performRequests(requests, CL_DEFAULT_TIMEOUT, nrDone, Logger::COMMUNICATION, true);
+  cc->performRequests(requests, CL_DEFAULT_LONG_TIMEOUT, nrDone, Logger::COMMUNICATION, true);
 
   // Now listen to the results:
   if (!useMultiple) {
@@ -2359,7 +2370,7 @@ int modifyDocumentOnCoordinator(
 
     // Perform the requests
     size_t nrDone = 0;
-    cc->performRequests(requests, CL_DEFAULT_TIMEOUT, nrDone, Logger::COMMUNICATION, true);
+    cc->performRequests(requests, CL_DEFAULT_LONG_TIMEOUT, nrDone, Logger::COMMUNICATION, true);
 
     // Now listen to the results:
     if (!useMultiple) {
@@ -2415,7 +2426,7 @@ int modifyDocumentOnCoordinator(
 
   // Perform the requests
   size_t nrDone = 0;
-  cc->performRequests(requests, CL_DEFAULT_TIMEOUT, nrDone, Logger::COMMUNICATION, true);
+  cc->performRequests(requests, CL_DEFAULT_LONG_TIMEOUT, nrDone, Logger::COMMUNICATION, true);
 
   // Now listen to the results:
   if (!useMultiple) {
diff --git a/arangod/RestHandler/RestReplicationHandler.cpp b/arangod/RestHandler/RestReplicationHandler.cpp
index 258d4959e0..7cf0205edd 100644
--- a/arangod/RestHandler/RestReplicationHandler.cpp
+++ b/arangod/RestHandler/RestReplicationHandler.cpp
@@ -1372,16 +1372,35 @@ Result RestReplicationHandler::processRestoreDataBatch(
     options.ignoreRevs = true;
     options.isRestore = true;
     options.waitForSync = false;
+    double startTime = TRI_microtime();
     OperationResult opRes =
         trx.remove(collectionName, oldBuilder.slice(), options);
+    double duration = TRI_microtime() - startTime;
     if (opRes.fail()) {
+      LOG_TOPIC(WARN, Logger::CLUSTER)
+        << "Could not delete " << oldBuilder.slice().length()
+        << " documents for restore: "
+        << opRes.result.errorMessage();
       return opRes.result;
     }
+    if (duration > 30) {
+      LOG_TOPIC(INFO, Logger::PERFORMANCE) << "Restored/deleted "
+        << oldBuilder.slice().length() << " documents in time: " << duration
+        << " seconds.";
+    }
   } catch (arangodb::basics::Exception const& ex) {
+    LOG_TOPIC(WARN, Logger::CLUSTER)
+      << "Could not delete documents for restore exception: "
+      << ex.what();
     return Result(ex.code(), ex.what());
   } catch (std::exception const& ex) {
+    LOG_TOPIC(WARN, Logger::CLUSTER)
+      << "Could not delete documents for restore exception: "
+      << ex.what();
     return Result(TRI_ERROR_INTERNAL, ex.what());
   } catch (...) {
+    LOG_TOPIC(WARN, Logger::CLUSTER)
+      << "Could not delete documents for restore exception.";
     return Result(TRI_ERROR_INTERNAL);
   }
 
@@ -1436,15 +1455,34 @@ Result RestReplicationHandler::processRestoreDataBatch(
     options.isRestore = true;
     options.waitForSync = false;
     options.overwrite = true;
+    double startTime = TRI_microtime();
     opRes = trx.insert(collectionName, requestSlice, options);
+    double duration = TRI_microtime() - startTime;
     if (opRes.fail()) {
+      LOG_TOPIC(WARN, Logger::CLUSTER)
+        << "Could not insert " << requestSlice.length()
+        << " documents for restore: "
+        << opRes.result.errorMessage();
       return opRes.result;
     }
+    if (duration > 30) {
+      LOG_TOPIC(INFO, Logger::PERFORMANCE) << "Restored/inserted "
+        << requestSlice.length() << " documents in time: " << duration
+        << " seconds.";
+    }
   } catch (arangodb::basics::Exception const& ex) {
+    LOG_TOPIC(WARN, Logger::CLUSTER)
+      << "Could not insert documents for restore exception: "
+      << ex.what();
     return Result(ex.code(), ex.what());
   } catch (std::exception const& ex) {
+    LOG_TOPIC(WARN, Logger::CLUSTER)
+      << "Could not insert documents for restore exception: "
+      << ex.what();
     return Result(TRI_ERROR_INTERNAL, ex.what());
   } catch (...) {
+    LOG_TOPIC(WARN, Logger::CLUSTER)
+      << "Could not insert documents for restore exception.";
     return Result(TRI_ERROR_INTERNAL);
   }
 
@@ -1490,15 +1528,34 @@ Result RestReplicationHandler::processRestoreDataBatch(
     options.ignoreRevs = true;
     options.isRestore = true;
     options.waitForSync = false;
+    double startTime = TRI_microtime();
     opRes = trx.replace(collectionName, builder.slice(), options);
+    double duration = TRI_microtime() - startTime;
     if (opRes.fail()) {
+      LOG_TOPIC(WARN, Logger::CLUSTER)
+        << "Could not replace " << builder.slice().length()
+        << " documents for restore: "
+        << opRes.result.errorMessage();
       return opRes.result;
     }
+    if (duration > 30) {
+      LOG_TOPIC(INFO, Logger::PERFORMANCE) << "Restored/replaced "
+        << builder.slice().length() << " documents in time: " << duration
+        << " seconds.";
+    }
   } catch (arangodb::basics::Exception const& ex) {
+    LOG_TOPIC(WARN, Logger::CLUSTER)
+      << "Could not replace documents for restore exception: "
+      << ex.what();
     return Result(ex.code(), ex.what());
   } catch (std::exception const& ex) {
+    LOG_TOPIC(WARN, Logger::CLUSTER)
+      << "Could not replace documents for restore exception: "
+      << ex.what();
     return Result(TRI_ERROR_INTERNAL, ex.what());
   } catch (...) {
+    LOG_TOPIC(WARN, Logger::CLUSTER)
+      << "Could not replace documents for restore exception.";
     return Result(TRI_ERROR_INTERNAL);
   }