Bypass InfiniBand rail autodetection

Custom_EasyBlocks/mpcframework.py

 from easybuild.easyblocks.generic.binary import Binary
+from easybuild.tools.filetools import write_file
 
 import os.path
 
@@ -25,3 +26,9 @@ class EB_MPCFramework(Binary):
             "MPCFRAMEWORK_DIR", self.installdir + 'share/mpcframework/cmake/')
 
         return txt
+
+    def post_install_step(self):
+        """Override network rail configuration by adding an MPC configuration file"""
+
+        write_file(os.path.join(self.installdir, "etc", "mpcframework", "rail.conf"),
+                   "LOWCOMM_NETWORKING_RAILS_IBMPI_DEVICE=mlx5_0")