diff --git a/lib/Alchemy/Phrasea/Model/Repositories/WorkerRunningJobRepository.php b/lib/Alchemy/Phrasea/Model/Repositories/WorkerRunningJobRepository.php
index a3b584058d..8d8655ec6a 100644
--- a/lib/Alchemy/Phrasea/Model/Repositories/WorkerRunningJobRepository.php
+++ b/lib/Alchemy/Phrasea/Model/Repositories/WorkerRunningJobRepository.php
@@ -102,4 +102,12 @@ class WorkerRunningJobRepository extends EntityRepository
     {
         return parent::getEntityManager();
     }
+
+    public function reconnect()
+    {
+        if($this->_em->getConnection()->ping() === false) {
+            $this->_em->getConnection()->close();
+            $this->_em->getConnection()->connect();
+        }
+    }
 }
diff --git a/lib/Alchemy/Phrasea/WorkerManager/Subscriber/RecordSubscriber.php b/lib/Alchemy/Phrasea/WorkerManager/Subscriber/RecordSubscriber.php
index d225a0c37a..c0df49717d 100644
--- a/lib/Alchemy/Phrasea/WorkerManager/Subscriber/RecordSubscriber.php
+++ b/lib/Alchemy/Phrasea/WorkerManager/Subscriber/RecordSubscriber.php
@@ -101,6 +101,9 @@ class RecordSubscriber implements EventSubscriberInterface
 
         $repoWorker = $this->getRepoWorker();
         $em = $repoWorker->getEntityManager();
+        // check connection an re-connect if needed
+        $repoWorker->reconnect();
+
         $workerRunningJob = $repoWorker->findOneBy([
             'databoxId' => $event->getRecord()->getDataboxId(),
             'recordId'  => $event->getRecord()->getRecordId(),
@@ -108,13 +111,15 @@ class RecordSubscriber implements EventSubscriberInterface
             'workOn'    => $event->getSubdefName()
         ]);
 
-        $em->beginTransaction();
-        try {
-            $em->remove($workerRunningJob);
-            $em->flush();
-            $em->commit();
-        } catch (\Exception $e) {
-            $em->rollback();
+        if ($workerRunningJob) {
+            $em->beginTransaction();
+            try {
+                $em->remove($workerRunningJob);
+                $em->flush();
+                $em->commit();
+            } catch (\Exception $e) {
+                $em->rollback();
+            }
         }
 
         $this->messagePublisher->publishMessage(
@@ -223,6 +228,9 @@ class RecordSubscriber implements EventSubscriberInterface
 
             $repoWorker = $this->getRepoWorker();
             $em = $repoWorker->getEntityManager();
+            // check connection an re-connect if needed
+            $repoWorker->reconnect();
+
             $workerRunningJob = $repoWorker->findOneBy([
                 'databoxId' => $event->getRecord()->getDataboxId(),
                 'recordId'  => $event->getRecord()->getRecordId(),
@@ -230,13 +238,15 @@ class RecordSubscriber implements EventSubscriberInterface
                 'workOn'    => $event->getSubdefName()
             ]);
 
-            $em->beginTransaction();
-            try {
-                $em->remove($workerRunningJob);
-                $em->flush();
-                $em->commit();
-            } catch (\Exception $e) {
-                $em->rollback();
+            if ($workerRunningJob) {
+                $em->beginTransaction();
+                try {
+                    $em->remove($workerRunningJob);
+                    $em->flush();
+                    $em->commit();
+                } catch (\Exception $e) {
+                    $em->rollback();
+                }
             }
 
             $this->messagePublisher->publishMessage(
diff --git a/lib/Alchemy/Phrasea/WorkerManager/Worker/SubdefCreationWorker.php b/lib/Alchemy/Phrasea/WorkerManager/Worker/SubdefCreationWorker.php
index a05d8a1aa7..1bf324943f 100644
--- a/lib/Alchemy/Phrasea/WorkerManager/Worker/SubdefCreationWorker.php
+++ b/lib/Alchemy/Phrasea/WorkerManager/Worker/SubdefCreationWorker.php
@@ -81,6 +81,7 @@ class SubdefCreationWorker implements WorkerInterface
 
                 // tell that a file is in used to create subdef
                 $em = $this->repoWorker->getEntityManager();
+                $this->repoWorker->reconnect();
                 $em->beginTransaction();
 
                 try {
@@ -108,14 +109,28 @@ class SubdefCreationWorker implements WorkerInterface
                 try {
                     $this->subdefGenerator->generateSubdefs($record, $wantedSubdef);
                 } catch (\Exception $e) {
-                    $em->beginTransaction();
                     try {
+                        $this->repoWorker->reconnect();
+                        $em->getConnection()->beginTransaction();
                         $em->remove($workerRunningJob);
                         $em->flush();
                         $em->commit();
                     } catch (\Exception $e) {
-                        $em->rollback();
                     }
+                } catch (\Throwable $e) {
+                    $count = isset($payload['count']) ? $payload['count'] + 1 : 2 ;
+                    $workerMessage = "Exception throwable catched when create subdef for the recordID: " .$recordId;
+
+                    $this->logger->error($workerMessage);
+
+                    $this->dispatcher->dispatch(WorkerEvents::SUBDEFINITION_CREATION_FAILURE, new SubdefinitionCreationFailureEvent(
+                        $record,
+                        $payload['subdefName'],
+                        $workerMessage,
+                        $count
+                    ));
+
+                    return ;
                 }
 
                 // begin to check if the subdef is successfully generated
@@ -170,7 +185,8 @@ class SubdefCreationWorker implements WorkerInterface
                 $this->indexer->flushQueue();
 
                 // tell that we have finished to work on this file
-                $em->beginTransaction();
+                $this->repoWorker->reconnect();
+                $em->getConnection()->beginTransaction();
                 try {
                     $workerRunningJob->setStatus(WorkerRunningJob::FINISHED);
                     $workerRunningJob->setFinished(new \DateTime('now'));
@@ -178,7 +194,17 @@ class SubdefCreationWorker implements WorkerInterface
                     $em->flush();
                     $em->commit();
                 } catch (\Exception $e) {
-                    $em->rollback();
+                    try {
+                        $em->getConnection()->beginTransaction();
+                        $workerRunningJob->setStatus(WorkerRunningJob::FINISHED);
+                        $em->persist($workerRunningJob);
+                        $em->flush();
+                        $em->commit();
+                    } catch (\Exception $e) {
+                        $this->messagePublisher->pushLog("rollback on recordID :" . $workerRunningJob->getRecordId());
+                        $em->rollback();
+                    }
+
                 }
             }
         }
diff --git a/lib/Alchemy/Phrasea/WorkerManager/Worker/WriteMetadatasWorker.php b/lib/Alchemy/Phrasea/WorkerManager/Worker/WriteMetadatasWorker.php
index 6c02078ac1..8ec819cb77 100644
--- a/lib/Alchemy/Phrasea/WorkerManager/Worker/WriteMetadatasWorker.php
+++ b/lib/Alchemy/Phrasea/WorkerManager/Worker/WriteMetadatasWorker.php
@@ -82,6 +82,7 @@ class WriteMetadatasWorker implements WorkerInterface
 
             // tell that a file is in used to create subdef
             $em = $this->getEntityManager();
+            $this->repoWorker->reconnect();
             $em->beginTransaction();
 
             try {
@@ -106,7 +107,24 @@ class WriteMetadatasWorker implements WorkerInterface
 
             $record  = $databox->get_record($recordId);
 
-            $subdef = $record->get_subdef($payload['subdefName']);
+            try {
+                $subdef = $record->get_subdef($payload['subdefName']);
+            } catch (\Exception $e) {
+                $workerMessage = "Exception catched when try to get subdef " .$payload['subdefName']. " from DB for the recordID: " .$recordId;
+                $this->logger->error($workerMessage);
+
+                $count = isset($payload['count']) ? $payload['count'] + 1 : 2 ;
+
+                $this->dispatch(WorkerEvents::SUBDEFINITION_WRITE_META, new SubdefinitionWritemetaEvent(
+                    $record,
+                    $payload['subdefName'],
+                    SubdefinitionWritemetaEvent::FAILED,
+                    $workerMessage,
+                    $count
+                ));
+
+                return ;
+            }
 
             if ($subdef->is_physically_present()) {
                 $metadata = new MetadataBag();
@@ -245,6 +263,7 @@ class WriteMetadatasWorker implements WorkerInterface
 
 
             // tell that we have finished to work on this file
+            $this->repoWorker->reconnect();
             $em->beginTransaction();
             try {
                 $workerRunningJob->setStatus(WorkerRunningJob::FINISHED);