Hi,

Our customer has is runnning SQL server standard and they
have clients that access the database.

We are moving them to SQL Server Enterprise in an
Active/Passive configuration.

My questions is what happens when the application connects
to the database, it starts doing a series of reads, and a
failure happens on the Active server in the cluster?

Will the client application have to be re-written in any
way to handle this failover? Will the application have
to "re-connect" to the database? Or will the failover be
transparent to the client application? How long will the
failover take?

Thanks,
Todd

A Cluster SQL failover looks exactly like the SQL server stopped and
restarted from the client's viewpoint. All connections will have to be
reestablished and any pending actions will need to be reissued.

--
Geoff N. Hiten
Microsoft SQL Server MVP
Senior Database Administrator
Careerbuilder.com

I support the Professional Association for SQL Server
www.sqlpass.org

<anonymous (AT) discussions (DOT) microsoft.com> wrote

Thanks Geoff. Approximately, how long does the failover
take?

That depends on several things such as the hardware, how many db's you have
and how many transactions need to be rolled forward or back. It could be 20
or 30 seconds or it could be minutes. That is something you need to test
and plan for.

--
Andrew J. Kelly SQL MVP


<anonymous (AT) discussions (DOT) microsoft.com> wrote

It depends. Hardware, memory size, how long an outstanding transaction has
been running, number and size of databases, recovery interval setting, and
reason for crashing all have an impact. As a general rule, figure out how
long your stand-alone system takes to shutdown and restart the SQL service
and add 30 seconds.

--
Geoff N. Hiten
Microsoft SQL Server MVP
Senior Database Administrator
Careerbuilder.com

I support the Professional Association for SQL Server
www.sqlpass.org

<anonymous (AT) discussions (DOT) microsoft.com> wrote