diff --git a/mongo/hooks/init b/mongo/hooks/init
index d2e6a60..916b9da 100755
--- a/mongo/hooks/init
+++ b/mongo/hooks/init
@@ -50,3 +50,63 @@ $MASTER_BASE_SERVICE_NAME:
   labels:
     - compose.config_hash=$config_hash
 "
+
+ensure_db_docker_running
+
+
+## ReplicaSet initialization
+
+cmd="rs.initiate({ _id: 'rs01', members: [ { _id: 0, host: '$SERVICE_NAME:27017' } ]})"
+debug "${WHITE}running:$NORMAL $cmd"
+
+out=$(ddb <<<"$cmd")
+
+if [[ "$out" == *"\"codeName\" : \"AlreadyInitialized\""* ]]; then
+    info "ReplicaSet already initialized."
+elif [[ "$out" == *"\"ok\" : 1"* ]]; then
+    info "ReplicaSet initialized. "
+else
+    err "ReplicaSet initialisation failed:"
+    echo "$out" >&2
+    exit 13
+fi
+
+
+## Enable read if db version >= 4.2
+
+if ! version=$(mongo:db:version); then
+    err "Couldn't get database version"
+    exit 1
+fi
+
+echo "Current mongo database version: '$version'." >&2
+
+if version_gt "$version" 4.1; then
+    cmd="db.getMongo().setSecondaryOk()"
+    debug "${WHITE}running:$NORMAL $cmd"
+
+    out=$(ddb <<<"$cmd") || {
+        err "Failed database command. Output:"
+        echo "$out" | prefix "  | " >&2
+        exit 1
+    }
+
+fi
+
+
+## This is some sort of migrating code and should be moved to upgrade
+## directory.
+
+major_version=${version%.*}
+
+cmd="db.adminCommand( { setFeatureCompatibilityVersion: \"${major_version}\" } )"
+debug "${WHITE}running:$NORMAL $cmd"
+
+out=$(ddb <<<"$cmd")
+if [[ "$out" == *"\"ok\" : 1"* ]]; then
+    info "Feature Compatibility set to ${major_version}. "
+else
+    err "Failed to set feature compatibility version failed:"
+    echo "$out" | prefix "  | " >&2
+    exit 13
+fi
diff --git a/mongo/hooks/mongo_database-relation-joined b/mongo/hooks/mongo_database-relation-joined
index 51ab9c4..60ca301 100755
--- a/mongo/hooks/mongo_database-relation-joined
+++ b/mongo/hooks/mongo_database-relation-joined
@@ -17,25 +17,6 @@ function version_gt() { test "$(printf '%s\n' "$@" | sort -V | head -n 1)" != "$
 ensure_db_docker_running
 
 
-## ReplicaSet initialization
-
-cmd="rs.initiate({ _id: 'rs01', members: [ { _id: 0, host: '$TARGET_SERVICE_NAME:27017' } ]})"
-debug "${WHITE}running:$NORMAL $cmd"
-
-out=$(ddb < <(echo "use $DBNAME";
-              echo "$cmd"))
-
-if [[ "$out" == *"\"codeName\" : \"AlreadyInitialized\""* ]]; then
-    info "ReplicaSet already initialized."
-elif [[ "$out" == *"\"ok\" : 1"* ]]; then
-    info "ReplicaSet initialized. "
-else
-    err "ReplicaSet initialisation failed:"
-    echo "$out" >&2
-    exit 13
-fi
-
-
 ## Enable read if db version >= 4.2
 
 if ! version=$(mongo:db:version); then
@@ -88,19 +69,3 @@ else
     exit 14
 fi
 
-
-major_version=${version%.*}
-
-## XXXvlab: why don't we do this initialisation in init ?
-cmd="db.adminCommand( { setFeatureCompatibilityVersion: \"${major_version}\" } )"
-debug "${WHITE}running:$NORMAL $cmd"
-
-out=$(ddb < <(echo "use $DBNAME";
-              echo "$cmd"))
-if [[ "$out" == *"\"ok\" : 1"* ]]; then
-    info "Feature Compatibility set to ${major_version}. "
-else
-    err "Failed to set feature compatibieplicaSet initialisation failed:"
-    echo "$out" | prefix "  | " >&2
-    exit 13
-fi