Today I encountered a problem with rpc connection.
backup was configured to backup local machine and not remote.
from the logs problem was that my local machine , trying to connect to it self by his name.
And in host file was another IP address for this name (host file manually configured) , reason for this configuration is one old program.
after removing this line in host file all started to work.
In this situation I can only advise to change in local machine backup RPC address to localhost , it will more correct.
But all this is only my opinion. -D