diff --git a/lib/database.js b/lib/database.js
index f183864..7d13433 100644
--- a/lib/database.js
+++ b/lib/database.js
@@ -268,7 +268,7 @@ function is_locked(lockfile, cb) {
 module.exports = {
   // initialize DB
   connect: function(database, cb) {
-    mongoose.connect(database, { useNewUrlParser: true, useCreateIndex: true, useUnifiedTopology: true }, function(err) {
+    mongoose.connect(database, { useNewUrlParser: true, useCreateIndex: true, useUnifiedTopology: true, useFindAndModify: false }, function(err) {
       if (err) {
         console.log('Unable to connect to database: %s', database);
         console.log('Aborting');
diff --git a/scripts/benchmark.js b/scripts/benchmark.js
index f9840c2..639aea3 100644
--- a/scripts/benchmark.js
+++ b/scripts/benchmark.js
@@ -18,7 +18,7 @@ dbString = dbString + '@' + settings.dbsettings.address;
 dbString = dbString + ':' + settings.dbsettings.port;
 dbString = dbString + "/IQUIDUS-BENCHMARK";
 
-mongoose.connect(dbString, { useNewUrlParser: true, useCreateIndex: true, useUnifiedTopology: true }, function(err) {
+mongoose.connect(dbString, { useNewUrlParser: true, useCreateIndex: true, useUnifiedTopology: true, useFindAndModify: false }, function(err) {
   if (err) {
     console.log('Unable to connect to database: %s', dbString);
     console.log('Aborting');
diff --git a/scripts/peers.js b/scripts/peers.js
index 8ad0186..ea092a2 100644
--- a/scripts/peers.js
+++ b/scripts/peers.js
@@ -17,7 +17,7 @@ dbString = dbString + '@' + settings.dbsettings.address;
 dbString = dbString + ':' + settings.dbsettings.port;
 dbString = dbString + '/' + settings.dbsettings.database;
 
-mongoose.connect(dbString, { useNewUrlParser: true, useCreateIndex: true, useUnifiedTopology: true }, function(err) {
+mongoose.connect(dbString, { useNewUrlParser: true, useCreateIndex: true, useUnifiedTopology: true, useFindAndModify: false }, function(err) {
   if (err) {
     console.log('Unable to connect to database: %s', dbString);
     console.log('Aborting');
diff --git a/scripts/sync.js b/scripts/sync.js
index 0b01f28..a8e7e4b 100644
--- a/scripts/sync.js
+++ b/scripts/sync.js
@@ -129,7 +129,7 @@ is_locked(function (exists) {
   } else {
     create_lock(function (){
       console.log("script launched with pid: " + process.pid);
-      mongoose.connect(dbString, { useNewUrlParser: true, useCreateIndex: true, useUnifiedTopology: true }, function(err) {
+      mongoose.connect(dbString, { useNewUrlParser: true, useCreateIndex: true, useUnifiedTopology: true, useFindAndModify: false }, function(err) {
         if (err) {
           console.log('Unable to connect to database: %s', dbString);
           console.log('Aborting');