There are few simple steps involved to monitor the replication actvites, as usual with Replication Monitor is useful to monitor the overall health of a replication topology. Replication Monitor provides detailed information on the status and performance of publications and subscriptions, allowing you to answer common questions, such as ( BOL ): Is my replication system healthy? Which subscriptions are slow? How far behind is my transactional subscription? How long will it take a transaction committed...(
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Read the complete post at http://sqlserver-qa.net/blogs/replication/archive/2007/08/23/1693.aspx