A few years ago I was lucky to be able to start working for a client that has Oracle RAC clusters. There we encountered lot’s of interesting issues, and one of them was that several client applications couldn’t seem to connect to the RAC cluster whenever a service was failed over to an other instance then the default.

The network environment was a bit different then I was used to work with. There are three domains in use: - domainA for the RAC and other servers, - domainB for the desktop pc’s and laptops - domainC for the citrix farm and the applications hosted there

The tnsnames.ora for domainB and domainC contained an entry like:

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