diff --git a/nixos/tests/installer.nix b/nixos/tests/installer.nix
index 64f98141cc0e..603dfbe224f9 100644
--- a/nixos/tests/installer.nix
+++ b/nixos/tests/installer.nix
@@ -120,7 +120,7 @@ let
       hdFlags =''hda => "harddisk", hdaInterface => "${iface}", '';
     in
     ''
-      createDisk("harddisk", 4 * 1024);
+      createDisk("harddisk", 8 * 1024);
 
       my $machine = createMachine({ ${hdFlags}
         cdrom => glob("${iso}/iso/*.iso"),