High availability options for Java based system (2 CI)?

[Former Member]

Hi All,

I am in the process of installing a highly available EP usage type of NW04s-SR1 on Windows 2003x64.

I am installing SCS and the database (Oracle) on a two node MSCS cluster. I will also be installing multiple dialog instances on different hosts to have redundancy.

What I am not clear about is the Central Instance. CI does not have a cluster installation option. It can be installed on a MSCS cluster node but has to be on local disk per the install document. So it will not be highly available.

Considering that only difference between the CI and DI seem to be SDM. Users are not really affected by CI not being available now that enqueue and the message server are in SCS.

I was thinking of installing 2 CIs for this system. I realize this requires multiple deployment/patch application but it provides redundancy. However, the installer does not allow this.

Is it possible to install 2 CIs in a Java based system for redundancy sake?

If not, what are the option for a highly available CI?

Thanks,

Farshid

[Former Member]

Farshid,

The reason there's no standard HA install option for the CI is that there's no really use-case for the requirment. True, SDM represents a SPOF for its functionality, but fundamentally it is simply an application that runs from the OS. You could restore the SDM to another host and run it just as easily from there - for instance from a DI host.

If you are determined to have the CI be HA then you could simply follow the steps described in several notes regarding manual (after the install) HA configuration and setup the CI instance to failover using MSCS and to be controlled by the cluster manager like the SCS. Of course you'd surely get some head scratching at support if you ever need help with such a configuration though.

I'd expect the work effort to be significantly greater than the value of the resulting capability to have the CI be highly available.

Nick