Determining Data Ownership - Red Hat DIRECTORY SERVER 8.1 - DEPLOYMENT Deployment Manual

How master copies of the data are maintained depends on the specific directory needs. However,
regardless of how data masters are maintained, keep it simple and consistent. For example, do
not attempt to master data in multiple sites, then automatically exchange data between competing
applications. Doing so leads to a "last change wins" scenario and increases the administrative
overhead.
For example, the directory is going to manage an employee's home telephone number. Both the LDAP
directory and a human resources database store this information. The human resources application
is LDAP-enabled, so an application can be written that automatically transfers data from the LDAP
directory to the human resources database, and vice versa.
Attempting to master changes to that employee's telephone number in both the LDAP directory and
the human resources data, however, means that the last place where the telephone number was
changed overwrites the information in the other database. This is only acceptable as long as the last
application to write the data had the correct information.
If that information was out of date, perhaps because the human resources data were reloaded from a
backup, then the correct telephone number in the LDAP directory will be deleted.
With multi-mater replication, Directory Server can contain master sources of information on more
than one server. Multiple masters keep changelogs and can resolve conflicts more safely. A limited
number of Directory Server are considered masters which can accept changes; they then replicate
the data to replica servers, or consumer servers.
safe failover in the event that a server goes off-line. For more information about replication and multi-
master replication, see
Synchronization allows Directory Server users, groups, attributes, and passwords to be integrated
with Microsoft Active Directory users, groups, attributes, and passwords. With two directory services,
decide whether they will handle the same information, what amount of that information will be shared,
and which service will be the data master for that information. The best course is to choose a single
application to master the data and allow the synchronization process to add, update, or delete the
entries on the other service.

2.3.6. Determining Data Ownership

Data ownership refers to the person or organization responsible for making sure the data is up-to-date.
During the data design phase, decide who can write data to the directory. The following are some
common strategies for deciding data ownership:
• Allow read-only access to the directory for everyone except a small group of directory content
managers.
• Allow individual users to manage some strategic subset of information for themselves.
This subset of information might include their passwords, descriptive information about themselves
and their role within the organization, their automobile license plate number, and contact information
such as telephone numbers or office numbers.
• Allow a person's manager to write to some strategic subset of that person's information, such as
contact information or job title.
• Allow an organization's administrator to create and manage entries for that organization.
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In replication, a consumer server or replica server is a server that receives updates from a supplier server or hub server.
Chapter 6, Designing the Replication
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Having more than on data master server provides
Process.
Determining Data Ownership
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