diff --git a/src/Symfony/Bundle/FrameworkBundle/Command/CacheClearCommand.php b/src/Symfony/Bundle/FrameworkBundle/Command/CacheClearCommand.php
index bbb71c15dd92a..650f36dc15b71 100644
--- a/src/Symfony/Bundle/FrameworkBundle/Command/CacheClearCommand.php
+++ b/src/Symfony/Bundle/FrameworkBundle/Command/CacheClearCommand.php
@@ -140,16 +140,34 @@ protected function execute(InputInterface $input, OutputInterface $output)
             }
         }
 
-        $containerDir = $fs->exists($warmupDir.'/'.$containerDir) ? false : $containerDir;
+        if (!$fs->exists($warmupDir.'/'.$containerDir)) {
+            $fs->rename($realCacheDir.'/'.$containerDir, $warmupDir.'/'.$containerDir);
+            touch($warmupDir.'/'.$containerDir.'.legacy');
+        }
 
-        $fs->rename($realCacheDir, $oldCacheDir);
-        $fs->rename($warmupDir, $realCacheDir);
+        if ('/' === \DIRECTORY_SEPARATOR && $mounts = @file('/proc/mounts')) {
+            foreach ($mounts as $mount) {
+                $mount = array_slice(explode(' ', $mount), 1, -3);
+                if (!\in_array(array_pop($mount), array('vboxfs', 'nfs'))) {
+                    continue;
+                }
+                $mount = implode(' ', $mount).'/';
 
-        if ($containerDir) {
-            $fs->rename($oldCacheDir.'/'.$containerDir, $realCacheDir.'/'.$containerDir);
-            touch($realCacheDir.'/'.$containerDir.'.legacy');
+                if (0 === strpos($realCacheDir, $mount)) {
+                    $io->note('For better performances, you should move the cache and log directories to a non-shared folder of the VM.');
+                    $oldCacheDir = false;
+                    break;
+                }
+            }
         }
 
+        if ($oldCacheDir) {
+            $fs->rename($realCacheDir, $oldCacheDir);
+        } else {
+            $fs->remove($realCacheDir);
+        }
+        $fs->rename($warmupDir, $realCacheDir);
+
         if ($output->isVerbose()) {
             $io->comment('Removing old cache directory...');
         }