webservice failover

[Joseph]

I have a web service (WS-A) running on multiple machines on a web farm and
each of WS-A is calling another web service (WS-B) where its path is defined
in the web.config file of WS-A. How can I implement failover for WS-B? i.e.
if WS-B fails on one machine how can I tell WS-A on ALL machines to switch
to use WS-B on another machine, assuming I have WS-B installed on multiple
machines. That mean I have to change the path of WS-B in all web.config
file of WS-A during runtime. How can I do it easily and efficiently?

thanks.
Joseph

 

[Jan Tielens]

That's a though one!

Out of the box there is no such mechanism implemented. Although in a web
application (I suppose a web service too), the web.config file get's
reloaded automatically.

If you're looking for a more advanced solution, you can look at the new WS-E
Addressing standard:
http://msdn.microsoft.com/webservic...ibrary/en-us/dnwebsrv/html/wsroutetowsadd.asp

 

[M. Posseth]

Maybe i am thinking just to "simple" but why wouldn`t you just use a
Loadbalanced failover cluster ( easy to acomplish with ms aplication
center 2000 )

i.o. w.
1 ip adress with multiple machines if one of the servers is down or to busy
another machine handles its load

i implemented this in our companny for our webservices and it works flawless
2 dual xeon machines with windows 2003 webserver edition and aplication
center 2000

in the future this could be scaled out to as much machines as you want ,
these machine scan even in different physical locations ( synced through the
internet )
etc etc etc