diff --git a/src/Symfony/Component/Cache/Tests/Adapter/RedisAdapterTest.php b/src/Symfony/Component/Cache/Tests/Adapter/RedisAdapterTest.php
index ec5cf61fd58bc..c448b685454ac 100644
--- a/src/Symfony/Component/Cache/Tests/Adapter/RedisAdapterTest.php
+++ b/src/Symfony/Component/Cache/Tests/Adapter/RedisAdapterTest.php
@@ -66,6 +66,9 @@ private function doTestCreateConnection(string $uri)
         $this->assertTrue($redis->isConnected());
         $this->assertSame(0, $redis->getDbNum());
 
+        $redis = RedisAdapter::createConnection('redis://'.$uri.'/');
+        $this->assertSame(0, $redis->getDbNum());
+
         $redis = RedisAdapter::createConnection('redis://'.$uri.'/2');
         $this->assertSame(2, $redis->getDbNum());
 
diff --git a/src/Symfony/Component/Cache/Traits/RedisTrait.php b/src/Symfony/Component/Cache/Traits/RedisTrait.php
index d452ee4cfc4d8..1eae909738b00 100644
--- a/src/Symfony/Component/Cache/Traits/RedisTrait.php
+++ b/src/Symfony/Component/Cache/Traits/RedisTrait.php
@@ -148,7 +148,7 @@ public static function createConnection(string $dsn, array $options = [])
         }
 
         if (isset($params['host']) || isset($params['path'])) {
-            if (!isset($params['dbindex']) && isset($params['path'])) {
+            if (!isset($params['dbindex']) && isset($params['path']) && '/' !== $params['path']) {
                 if (preg_match('#/(\d+)$#', $params['path'], $m)) {
                     $params['dbindex'] = $m[1];
                     $params['path'] = substr($params['path'], 0, -\strlen($m[0]));