What version(s) are you using? Have you run checkSysConf on the machines to ensure that they meet the patch requirements? Can you look at cdsNameServer and cdsMsgServer processes - are they coming from the appropriate release (if you are using a mixture of versions) for the version of layout that you are using?
Seems like it might be a communication related issue, so check that the networking to/from the remote machine is okay.
Hope this helps to narrow down the scope of the problem.