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Most of the interesting and relevant information will usually be found in the shibd.log, particularly SAML-related problems, Metadata issues, and most security issues.
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An additional log is configured from within the shibd.logger setup file, and typically written to transaction.log. The transaction log supports an extensible event model that applies a formatting string to each event (via the tranLogFormat setting in the <OutOfProcess><OutOfProcess> element). A list of supported event types and fields follows.
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