The OOB Server does not need DNS working on your network. However, if you enable the OOB configurable parameters "ReverseLookup" then the OOB server will perform a reverse lookup on the client's IP address to obtain the client machine name. In this case DNS must be working and your resolver library must be able to do the reverse lookup or it can result in long connection times.
The OOB client only needs to resolve a machine name into an IP address if you set the Server attribute in your odbc.ini/registry to a machine name. You can avoid this by referring to the server machine's IP address instead.
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