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SQL Server 2005 mirroring question..

I have set my database to mirror without a witness.. (sorry dont have a 3th server for acting as witness)

Now basicly how would failover work if my principal server goes down??

Can I just set my application to  start to use the mirror server or is there any other action required before my application can switch over to the mirror server??

And what happends if my principal server comes up again will it copy all the data made at the mirror server back to the principal? or will it overwrite my mirror with the latest data on the principal??

I just want to create a basic failover scheme here.. That if one server goes down the backup server takes over until I restored the main server again.. I'm going pure for redudancy here..

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ro8inmorgan
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ro8inmorgan
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SireesCommented:
<<Can I just set my application to  start to use the mirror server or is there any other action required before my application can switch over to the mirror server??>>

You don't have to do any actions. You can set your application  to start using mirror.

<<And what happends if my principal server comes up again will it copy all the data made at the mirror server back to the principal? or will it overwrite my mirror with the latest data on the principal??>>

When Principal server comes up again, it will act as a mirror. It will have all the up todate transactions made on your mirror.
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ro8inmorganAuthor Commented:
sweet..

and what will happend in case of a short disconnect of the prinicipal??.. how fast will the mirror become the principal server and the principal server the mirror...

And if this works like this without witness then what is the witness server for??


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SireesCommented:
<<And if this works like this without witness then what is the witness server for??
>>

I am sorry..I missed the part that you don't have the witness server..

Now to answer your questions (with out the witness server)..

<<Can I just set my application to  start to use the mirror server or is there any other action required before my application can switch over to the mirror server??>>>>

You have to do a manual failover (automatic failover is not possible without witness) to the mirror and set your application to use the mirror server.

<<And what happends if my principal server comes up again will it copy all the data made at the mirror server back to the principal? or will it overwrite my mirror with the latest data on the principal??>>

If you are using high protection mode, when Principal server comes up again, it will act as a mirror. It will have all the up todate transactions made on your mirror.

In High performance mode, it does not care if writes are synchornised on both the servers. When using this option, you assume that everything is going to complete successfully on the mirror and failover is a manual process


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