How to instantiate an ICE Object redundantly?

[vsonnathi]

Hi,

I read the following in the documentation and could find any references to it later in the document

"A single Ice object can be instantiated in a single server or, redundantly, in
multiple servers. If an object has multiple simultaneous instantiations, it is still
a single Ice object."

Can someone please point or give some info on how to do this?

Thanks,
--Venkat.

[mes]

Hi,

It's really quite simple:

• Two or more servers create a servant with the same identity
• The proxy for the Ice object contains the endpoints for all of the servers
• The client selects one of the endpoints at random when establishing a connection
• In the case of a network error, the client automatically retries all of the endpoints when attempting to reestablish a connection

Take care,
- Mark

[vsonnathi]

Hi,

Thanks for the info.

I have to maintain a cache (Search Engine results) for the service and would like to go to the same server for further requests for efficiency purposes. Can we do this with ICE - what I am looking for is for the first request go to a available server and from then on try going to the same server if available.

Thanks,
--Venkat.

[mes]

Hi,

Once established, Ice will continue to use a connection for subsequent requests. However, Ice may transparently close and reopen connections, and that could result in a new connection to a different server.

One way to implement your requirement is with a two-tiered system: the client uses a multi-endpoint proxy to send a request to a randomly-selected factory, and the factory returns a proxy for an object in a particular server (a "session" concept).

Take care,
- Mark

[ganzuoni]

Originally posted by mes
Hi,

Once established, Ice will continue to use a connection for subsequent requests. However, Ice may transparently close and reopen connections, and that could result in a new connection to a different server.

One way to implement your requirement is with a two-tiered system: the client uses a multi-endpoint proxy to send a request to a randomly-selected factory, and the factory returns a proxy for an object in a particular server (a "session" concept).

Take care,
- Mark

Hi Marc,
it could be nice (i.e. transparent) if all the job could be done by a
Locator implementation.
This special Locator, for each findObjectById, could return a proxy obtained
merging the endpoints (in randomized order, round-robin ?)
of registered replicas.
Obviously, client-side Ice internal should not alter the order of
endpoints received by the Locator.
More, LocatorInfo should not cache endpoints. This is particularly
important in multi-threaded client such as servlet container.
In this way, the endpoint list attached to a reference is used
just for failover purposes and not for load-balancing, that is left
to the Locator.

But, maybe, I am missing a lot of other issues concerning connection
management....

Guido.