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    <p>Consider what the Windows Cluster monitor does for a SQL Server Cluster resource: it actually connects and runs a dummy query (<code>SELECT @@version</code>). This indicates that the SQL is running, is actively listening for requests, and is able to run a request and return a result. For the clustering monitor the response to this query is the 'heartbeat' of the server and if it fails to get a response, for whatever reason, it may initiate a cluster failover.</p> <p>Only connecting to TCP has several drawbaks in my opinion:</p> <ul> <li>it omits non-TCP protocols like local shared memory (LPC) or remote net pipes (SMB)</li> <li>it requires hard codded TCP port number as opposed to let the instance port listening auto-discovery do its work (SQL Browser and friends)</li> <li>it only establishes that the OS level socket can be established, it does not validate that the SQL Server itself is in a runnable state (non-yielding scheduler might block network IO requests acceptance, scheduler overload and worker starvation may do the same, memory resource exhaustion etc etc).</li> </ul> <p>Unfortunately there is no way to get a notification from SQL Server itself of saying 'hey, I'm active, won't you send some requests?'. I don't know all the details of your fat client ('thick app'), but perhaps you should investigate a different metaphor: clients do <em>all</em> work locally, on SQL Express instances, and these instances synchronize the data when the server is available. <a href="http://msdn.microsoft.com/en-us/library/ms345108%28SQL.90%29.aspx" rel="nofollow noreferrer">Service Broker</a> was designed specifically with this connection retry mode and it would hide the server availability due to its asynchronous loosely coupled programming API.</p>
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    1. POHow to Implement Exchange like availability monitoring of internal SQL Server
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    1. USRemus Rusanu
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    1. POHow to Implement Exchange like availability monitoring of internal SQL Server
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    1. COThis is the only way to tell, reliably, if sql server is in fact up and running. If you are simply connecting to 1433, the SQL Browser service might be available, but the server itself isn't responding for some reason.
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      1. USNotMe
    2. CO@Remus: Allow me to paraphrase your answer for my own understanding. I should have a method that connects and runs a dummy query. If it fails to run(??) or returns a certain result I am NOT Connected otherwise I am? You are saying I will still be using a `Timer` to poll my server and it sounds like a `Try/Catch` as well. I will just be replacing my `TcpClient.Connect()` call with my Dummy Query. Am I correct?
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      1. USRefracted Paladin
    3. CO@Remus: When you say 'different metaphor', could you elaborate? From that point on I do not understand what you are trying to say to me. Thank you for your time.
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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