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What is a sql server cluster

Hi,
Can someone explain to me simply "what is a sql server cluster"?
Avatar of Guy Hengel [angelIII / a3]
Guy Hengel [angelIII / a3]
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a server cluster (does not only apply to SQL Server), is nothing else than 2 (or more) Boxes, with shared stored (disks), running both the same software (ie sql server), where the passive node will server as failback box when the active node fails (goes down).

so, say you have 2 servers (nodes), in a usual activ-passive config, both boxes have sql server installed, but only 1 has the database(s) for a given application (active), the other has nothing (passive node).
if the active box fails, the cluster software will perform the failover, and the software (SQL Server) will continue running on the previously passive box.


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ASKER

Great answer thanks.  I have one bit of what you said I don't understand

You say if one fails the other will take over, but the databases are on only one server.   If the active server fails how then does the passive server access the databases on the failed active server?

Thanks



>You say if one fails the other will take over, but the databases are on only one server.
the databases (including master, msdb... etc) have to be located on the shared storage, so can be accessed by the other server also.
when you install sql server in the cluster, hence both nodes, both will be able to work with all the databases.
consider it like it's only 1 logical installation of sql server on the 2 nodes.
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ASKER

Ok great but where are things like DTS packages stored?  Active Node, passive node or Sharded storage?
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Avatar of Guy Hengel [angelIII / a3]
Guy Hengel [angelIII / a3]
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ASKER

Doh!...of Course!

Great answers thanks!!