Version 3.1-en Solaris 10 Container Guide - 3.1 2. Functionality Effective: 30/11/2009
2.1.9. Solaris container cluster (aka "zone cluster")
[hs] In autumn 2008, within the scope of the Open HA Cluster Project, zone clusters were
announced. The latter has also been available since Sun Cluster 3.2 1/09 in a commercial product as
Solaris Container Cluster. A Solaris Container Cluster is the further development of the Solaris zone
technology up to a virtual cluster, also called "zone cluster”. The installation and configuration
of a container cluster is described in the Sun Cluster Installation Guide
[http://docs.sun.com/app/docs/doc/820-4677/ggzen?a=view].
The Open HA Cluster provides a complete, virtual cluster environment. Zones as virtualized Solaris
authorities are used as elements. The administrator of such an environment can see and notice
almost no difference to the global cluster that is virtualized here.
Two principal reasons have advanced the development of virtual cluster technology:
•the desire to round off container technology
•the customer requirement to be able to run Oracle RAC (Real Application Cluster) within a
container environment.
Solaris containers, operated by Sun Cluster, offer an excellent possibility to operate applications
safely and with high availability in Solaris containers. Two options, Flying Containers and Flying
Services, are available for implementation.
A clean separation in system administration allows container administration t o be delegated to the
application operators who install, configure and operate their application within a container. It was
indeed unsatisfactory for an application operator to have administrator privileges in his containers but,
on the other hand, to be limited in handling the cluster resources belonging to his zone.
In the cluster implementation prior to Sun Cluster 3.2 1/09, the cluster consisted mainly of the
components installed, configured and also running in the global zone. Only a very small number of
cluster components were actually active within a container, and even this allowed very limited
administrative intervention only.
Now, virtual clusters make the zone administrator feel that he has almost complete control of his
cluster. Restrictions apply t o services that continue to exist only once in the cluster, such as e.g.
quorum devices or even heartbeats.
Oracle RAC users could not understand that this product could not simply be installed and operated
within a container. One has to know, however, that Oracle CRS, the so-called Oracle Clusterware –
an operating system independent cluster layer – requires rights that the original safety concept of
Solaris containers did not delegate to a non-global zone. Since Solaris 10 5/08 it is, however, possible
to administer network interfaces even within a zone such that Oracle CRS can be operated there.
The goal of providing a cluster environment that does not require any adjustments of applications
whatsoever has been achieved. Even Oracle RAC can be installed and configured just like in a
normal Solaris instance.
Certification of Oracle RAC in a Solaris Container Cluster is currently (June 2009) not yet finalized.
However, Sun Microsystems offers support for such an architecture.
It is also p ossible to install Oracle RAC with CRS in a Solaris container without a zone cluster but it
will not yet be certified. The disadvantage of such a configuration consists in the fact that solely
exclusive-IP configurations can be used, which unnecessarily increases the number of required
network interfaces (if not using VLAN interfaces).
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