The quorum mechanism is configured for each catalog service.
You must enable the quorum mechanism on all of the catalog servers
in the catalog service domain.
About this task
The quorum mechanism is disabled by default. Enable the quorum
mechanism in the following scenarios:
- When your catalog service domain spans a network that is unpredictable
or unstable. This type of network might span multiple data centers.
- When you want to prevent the data grid from self-healing during
a brownout on the network, and instead temporarily pause data grid
operations from occurring.
You can leave the quorum mechanism disabled if your catalog service
domain is contained within a single data center, or is on a local
area network (LAN). In this type of configuration, default heart beating
is used and brownouts are assumed to be shorter than 10 seconds. Because
the detection period is approximately 30 seconds, any short brownouts
that occur do not cause placement changes to occur in the data grid.
If
you enable quorum, all the catalog servers must be available and communicating
with the data grid to conduct placement operations. If a network brownout
occurs, placement is paused until all the catalog servers are available.
If a data center failure occurs, manual administrator actions are
required to remove the failed catalog server from the quorum.
Results
By setting the quorum mechanism to be enabled on the catalog
servers within a catalog service domain, all the catalog servers must
be available for data grid placement operations to occur. In the event
of a short network brownout, placement operations are temporarily
stopped until all the catalog servers in the quorum are available.
You
can add additional catalog servers to the quorum by repeating these
steps.