Usually a BizTalk administrator will need to monitor the database jobs that are running to ensure they are still running successfully, and depending on the frequency of the jobs he may need to delete the oldest backup files. Usually a BizTalk administrator will need to also monitor the event log or a custom log for errors that might result from permission changes and/or availability issues. In a large environment with a system monitoring tool like SCOM, alerts will be setup for BizTalk systems that notify the administrator of ongoing issues when they occur. Usually a BizTalk administrator will also need to work closely with a BizTalk developer to facilitate debugging.
There is a good course on BizTalk administration available from QuickLearn – they have a good list of some of the tasks on their course outline – http://www.quicklearn.com/class_BizTalk_for_Administrators.aspx.
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