diff --git a/src/Symfony/Component/Cache/Tests/Adapter/RedisAdapterTest.php b/src/Symfony/Component/Cache/Tests/Adapter/RedisAdapterTest.php
index 7bb16573db32f..b020ddc9f43a8 100644
--- a/src/Symfony/Component/Cache/Tests/Adapter/RedisAdapterTest.php
+++ b/src/Symfony/Component/Cache/Tests/Adapter/RedisAdapterTest.php
@@ -96,6 +96,7 @@ public function provideFailedCreateConnection(): array
             ['redis://localhost:1234'],
             ['redis://foo@localhost'],
             ['redis://localhost/123'],
+            ['redis:///some/local/path'],
         ];
     }
 
diff --git a/src/Symfony/Component/Cache/Traits/RedisTrait.php b/src/Symfony/Component/Cache/Traits/RedisTrait.php
index 5365a53b18f15..649d50704ff2b 100644
--- a/src/Symfony/Component/Cache/Traits/RedisTrait.php
+++ b/src/Symfony/Component/Cache/Traits/RedisTrait.php
@@ -151,7 +151,7 @@ public static function createConnection($dsn, array $options = [])
                 if (preg_match('#/(\d+)$#', $params['path'], $m)) {
                     $params['dbindex'] = $m[1];
                     $params['path'] = substr($params['path'], 0, -\strlen($m[0]));
-                } else {
+                } elseif (isset($params['host'])) {
                     throw new InvalidArgumentException(sprintf('Invalid Redis DSN: "%s", the "dbindex" parameter must be a number.', $dsn));
                 }
             }