at this time im facing a desing problem. i need to emulate a clustered enviroment with a C# windows services.
My windows services invokes every day at the same time (using quartz for .net) a web service which is resposible for duty works. The problem is that this enviroment is redundant in order to guaranteed availabilty but doesn’t has automatic failover support, i mean when one site is down, user simply goes to the other (i know this is not good, but actually this is our backup enviroment, so we don’t mind to do this).
Both enviroment has this configuration: Web Server – App Server – DB Server, and DB Server 1 has a merge replication over DB Server 2.
The thing is, i need to guaranteed that just one windows service (Scheduler) fires up at the configured time, but when one of them is not available the other must be ready to invoke the web services.
i will appreciate any clue that you can provide me, in order to solve this issue in a better way.
Cheers.
Normally this is handled using SQL Server clustering. It isn’t easy, but that is your best option. When using that you don’t need to make any changes to your .NET 2.0 or later application. (Early versions of .NET would require you to manually flush the connection pool.)
Your second option would be to create a small service that acts as the traffic cop. This service would watch the two databases and decide which connection string to use at any given time. Applications would have to ping this service on a regular basis to learn which connection to use.