diff --git a/test/Microsoft.AspNetCore.Server.HttpSys.FunctionalTests/Properties/AssemblyInfo.cs b/test/Microsoft.AspNetCore.Server.HttpSys.FunctionalTests/Properties/AssemblyInfo.cs
index 6d9ec40..0d585d3 100644
--- a/test/Microsoft.AspNetCore.Server.HttpSys.FunctionalTests/Properties/AssemblyInfo.cs
+++ b/test/Microsoft.AspNetCore.Server.HttpSys.FunctionalTests/Properties/AssemblyInfo.cs
@@ -2,6 +2,8 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using Microsoft.AspNetCore.Testing.xunit;
+using Xunit;
 
 [assembly: OSSkipCondition(OperatingSystems.MacOSX)]
-[assembly: OSSkipCondition(OperatingSystems.Linux)]
\ No newline at end of file
+[assembly: OSSkipCondition(OperatingSystems.Linux)]
+[assembly: CollectionBehavior(DisableTestParallelization = true)]
\ No newline at end of file