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Under normal circumstances, the space in the log file is regularly reused, with space being made available for reuse through a process called Newtablinkaliaslog truncationurlhttp://technet.microsoft.com/en-us/library/ms189085(v=sql.105).aspx. When log truncation cannot occur for some reason, the log file will attempt to grow if autogrow is enabled and the file has not reached its maximum size. When a log file becomes full and can no longer grow, attempts to modify or add data to the database will produce an error: the database will essentially become read-only.

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