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82 Chapter 7. Using the Cluster Configuration System
7.5.2. Local CCA Files
An alternative to both a CCA device and a CCS server is to replicate CCA files on all cluster nodes.
Note
Care must be taken to keep all the copies identical.
A CCA file is created using the same steps as for a CCS server. The CCA file is manually copied to
all cluster nodes.
7.5.2.1. Starting the CCS Daemon
When the CCS daemon is started on each node, it must be given the location of the local copy of the
CCA file.
7.5.2.2. Usage
ccsd -f File
File
Specifies the local copy of the CCA file.
7.5.2.3. Example
This example starts
ccsd
on a node using a local copy of a CCA file.
ccsd -f /etc/sistina/ccs-build/alpha.cca
7.6. Combining CCS Methods
The shared block-device methodology described at the beginning of this chapter is the
recommended method for storing CCS data (Section 7.1 Creating a CCS Archive and
Section 7.2 Starting CCS in the Cluster ). The advantages are that there is no server point-of-failure
and that updates to the CCS archive happen atomically.
However, not every cluster has every node connected to the shared storage. For example, a clus-
ter may be built with external lock servers that do not have access to the shared storage. In that
case, the client/server methodology (Section 7.5.1 CCA File and Server ) could be employed, but that
approach introduces a server point-of-failure. Also, local file archives could be used on each node
(Section 7.5.2 Local CCA Files ), but that approach makes updating the CCS archives difficult.
The best approach for storing CCS data may be a combination of the shared-device method and the
local-files method. For example, the cluster nodes attached to shared storage could use the shared-
device method, and the other nodes in the cluster could use the local-files approach. Combining those
two methods eliminates the possible point-of-failure and reduces the effort required to update a CCS
archive.