Recently, we've suddenly starting getting this error message when users are trying to connect to our production database from remote clients. However, by the time we are notified we can login without any problems. It is very hard to diagnose this error as we cannot reproduce it. Occasionally, this occurs (several times per week) and is causing production jobs to fail (they have to restarted and usually they are fine). We are using ONames and Oracle8i on Solaris. Has anyone encountered a similar situation and any recommendations?