A new administrator is performing fallover testing on a two-node cluster and is concerned that the cascading resource group belonging to Node ’A’ did not reintegrate properly after the cluster was restarted on Node ’A’. A stable cluster is reported by clstat，and clRGinfo reports the resource group online on Node ’B’. 
What type of configuration would cause this type of behavior？（）  

Company.com with a newly installed cluster has been checking the logfiles to determine if the  cluster has had any recent activity. The non-IP RS232 heartbeat connection seems to be having a difficulty. The serial network goes down，and then a couple of minutes later comes back up again. This pattern is repeated many times in the log. 
If this system was installed without regard to best practices， what is the most likely problem with the serial network？（）