[omniORB] running omninames in a windows-cluster

[Duncan Grisby]

On Thursday 2 May, Empting Arnd wrote:

> we would like to run omninames in a window2k cluster. 
> At first glance it seems easy because the binding information is held in a
> file and the two cluster-services can share that file. But if you start
> omninames on cluster-server one it will make a file
> "omninames-cluster-server-one.log" and on the second the name of the
> data-file is "omninames-cluster-server-two.log". 

The problem with the Naming service is that each NamingContext within
it is a CORBA object with its own object reference. The IOR embeds the
host and port of the server. When omniNames starts up, it recreates
the complete arrangement of NamingContexts, with their previous object
references, in case parts of the Naming service have been remembered
elsewhere. To be able to do that, it has to run on the same machine it
ran on before.

If you just try renaming or copying the log file, you'll find that it
doesn't work since the log refers to the objects on the original
machine. You can convert the IORs in the log file to contain a
different host name with a script that uses the convertior tool, but
that's not a practical solution for regular use.

It would be possible to come up with a different logging mechanism
that would make it much easier to replicate omniNames instances, but
it's not a small change, and it would cause problems with federated
naming graphs.

Cheers,

Duncan.

-- 
 -- Duncan Grisby         --
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