Our APS.Net eCommerce application runs on a web server that reaches SQL

Server in our network. We are looking for options to have two different
web
servers and Database servers so that if we have a problem in one web
server
or a database server, the other will still continue to serve our
clients.
Questions:
1. Is this the way everybody does to create backup for the system?
2. Does SQL Server support this, if yes, how?
3. Are we expecting change in web-based application for this?
Thanks for your help.

Jim,

There are several different ways to do this. (Although this is not a
complete list)

1. You could implement Transaction Log shipping from one Database to
another. This can only be used when the Database uses Full Recovery
Mode. Transaction Logs are shipped from the Primary Server to the
secondary - they are then loaded in to the secondary Database with No
Recovery. If the Primary should fail - you restore the last
Transaction Log to the Secondary using "With Recovery". The Secondary
Database is now operational up to the point of failure.

2. You could implement a SQL Server Cluster. A simple example would
be having two servers sharing a Raid Array - with SQL Server on this
array. One Server would be the Primary Node, the other the Secondary
Node. If the Primary Node fails, processing switches over the
Secondary Node. This is a Active/Passive cluster.

Another situation is the Active/Active Cluster. This is where you
create two virtual servers and each server is the Primary Node for one
virtual server and a secondary node for the other Virtual Server. The
downside is the considerable cost to implement this. In addition to
the extra licencing, you'll also need the Servers to be pretty high
spec as in the event of failure there will be one server doing the
processing od two servers.

3. You could implement Replication. There are various types of
Replication, the main types being, Snapshot, Merge & Distributed
Transactions. The type of Replication used depends on the latency
(time it takes to replicate data). Distributed Transaction being the
lower latency (Replication is almost instant) to Snapshot replication.
This type of replication does exactly what is says - takes a snapshot
at given times and replicates the data to the other database.

I hope this helps in some way as to which route you take.

Barry