Java clients load balancing/failover of Configuration Service

Question

Hello,

Is it  possible for Java clients to take advantage of load balancing/failover? 

As I see it is possible for NET clients because of they must use base classes.

What about Java clients or non-NET clients?

Thanx

Answer 1

Currently, the answer is no since the load balancing is implemented in the client .NET base class provided with the Config Service.  So Java clients would load balance against .NET services through a mechanism like big ip (hardware load balancer) or Windows Network Load Balancing (software load balancer that is integrated into Windows Server).

Of course there are disadvantages to the approach Config Service takes; however also advantages (in intranet classic RMI-style deployment scenarios) since the clients can make more intelligent decisions about what to do/how to failover than if using a router or some sort of server-side network load balancing.

However, two things to note:

1)  .NET clients implementing Config Serrvice can load balance/failover against Java services.
2)  The entire Config Service protocol stack is implemented in Windows Communication Foundation; since this is based on open Web Service/SOAP stack; you could build a Java client capable of receiving/sending service node notifications; but this would be a bit of work.
3)  In next release, I hope to have a "client-light" implementation that does not require implementation of config service; doing a Java client as well might be interesting. 

-Greg

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Greg Leake, Microsoft

Answer 2

Thank you Greg.

Yet another qstn:

We have a VC++ application, which used COM objects etc. and on other side we are developing WCF service, we are going to use

Config Service.

I need to call  WCF service methods from VC++ application.

What is a better way to do this to take advantages of Config Service, clustering, load balancing?

Regards.

Answer 3

From VC++ I am really not sure.  Currently the client needs to fully implement the config service, meaning repository, use of config service shared libraries, etc.  All the libraries are managed code (C#); and could be used by C#, VB.NET or any language implemented on the .NET Framework CLR.  So you would somehow need to introduce managed code libraries to your C++ app; which I know is possible but I have never done myself.  Then, the VC++ app could make use of the generated client class that has the load balancing/failover logic. 

-Greg

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Greg Leake, Microsoft