I am trying to make sure that all host-aliases that exist in file1 also exist in file2.

and

I need to know if the host-alias exists under the same "host id" in both files.

are very different problems. Unfortunately, I've already spent too much time answering the first question and cannot help you at this time.

In reply to Re^3: Difficulty Mapping Data by ikegami
in thread Difficulty Mapping Data by walkingthecow

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