[Xymon] "xymond" column is blank/dash

Hi

I can't work this out. I have two practically identical Xymon (4.3.0) servers successfully monitoring a few other servers. Both have identical hosts.cfg files and present identical results for all monitored hosts, as well as themselves.

The strange thing is that the "xymond" column for the first server is green but is a dash "-" for the second server. It looks the same on both servers. I can't see anything in the logs to indicate a problem. The only configuration difference between the two servers is the setting of XYMONSERVERHOSTNAME and XYMONSERVERIP in xymonserver.cfg. Can anyone suggest why the difference, or where to look for problems?

Cheers Jeremy