[Linux-cluster] ANNOUNCE: Heartbeat Cluster Resource Manager Ported to OpenAIS

[Andrew Beekhof]

Just as OCFS2 and GFS2 are converging on some of their in-kernel  
components, I am happy to announce that similar convergence is  
starting to occur elsewhere in the cluster stack.

Over the last few months, Red Hat and SUSE engineers have been working  
together to port Heartbeat's powerful Cluster Resource Manager (CRM)  
to run natively on top of OpenAIS.

OpenAIS is an OSI Certified implementation of the Service Availability  
Forum Application Interface Specification (AIS) and forms the  
foundation of the open source clustering stack shared by Novell/SUSE,  
Red Hat, and Oracle.

Running natively on top of OpenAIS gives the cluster manager access to  
the many features it provides:
- event service
- message service
- checkpoint service
- distributed locking service
- cluster membership service
- extended virtual synchrony service
- cluster closed process group service

More importantly, it means that applications being managed by the  
cluster can also make use of such services and can do so on  
forthcoming versions of both RHEL and SLES.

Applications that already use OpenAIS can also be managed by the CRM  
more reliably than before - since by using the same communication and  
membership services, they will always have the same view of the cluster.


There are a number of items yet to be completed, the most critical  
being to plug the cluster manager into to a fencing subsystem, however  
2, 4 and 6 node clusters have been responding well to automated  
testing (which is incredibly harsh on the cluster) and the software  
has been given a clean bill of health by Valgrind.  This is of course  
in addition to the rigorous release testing of OpenAIS itself.


Completing the port is a top priority for SUSE's cluster team in 2008.


Packages for OpenAIS^ and the CRM^^ can be found for most major  
distros on the OpenSUSE Build Service:
      http://download.opensuse.org/repositories/server:/ha-clustering/

Just look for packages with an openais prefix.

More information on the CRM^^ and OpenAIS^ can be found at http://linux-ha.org/v2 
  and http://www.openais.org respectively.




^ The OpenAIS packages include a couple of required patches that  
haven't yet been shipped by the OpenAIS project.  When configuring  
OpenAIS, one also needs to include the following in openais.conf so  
that the child process that controls resources has permission to do so.
aisexec {
	user:	root
	group:	root
}

^^ Currently, the openais-crm packages can only be used with OpenAIS.   
Choosing a communications layer at run-time is possible but not yet  
implemented.