diff --git a/src/Handler.php b/src/Handler.php
index 85fdf2eb1fef5e5861854cc267a98f5df2a714cc..15c76d26457789b6261000d1f92098737cfbbe53 100644
--- a/src/Handler.php
+++ b/src/Handler.php
@@ -233,7 +233,7 @@ class Handler extends BaseHandler {
     $this->config->setValue('relatedprojectdomains', $relatedprojectdomains, FALSE);
 
     // Get ID of Docker group
-    $docker_group_id = shell_exec('stat -c "%g" /var/run/docker.sock');
+    $docker_group_id = trim(shell_exec('stat -c "%g" /var/run/docker.sock'));
     $this->config->setValue('docker_group_id', $docker_group_id, FALSE);
 
     if ($alerta_api_key = getenv('ALERTA_APIKEY')) {