How many Publisher servers can be added to a UCM cluster? (Select the best answer.)

A.
one

B.
two

C.
six

D.
eight

Explanation:
A Cisco Unified Communications Manager (UCM) cluster supports one Publisher server. The Publisher server
in a UCM cluster has two roles. It holds the master writable copy of the IBM Informix database for the cluster,
and it acts as a Trivial File Transfer Protocol (TFTP) server for IP phone configuration downloads. ThePublisher server is the only server that contains a writable copy of the IBM Informix database that stores
directory numbers (dns), calling permissions, route plans, and other information. The Publisher server
replicates the data that is stored in the master database to the Subscriber servers, all of which then store their
own readonly copies of the database.
A UCM cluster can support up to eight Subscriber servers. Subscriber servers typically handle call routing, dial
tone, receiving digits, and the streaming of onhold music in a UCM cluster. In medium to large environments,
the Subscriber servers perform most of the work in connecting and maintaining calls so that the performance of
the Publisher server is not hindered. A UCM cluster is an environment that contains a Publisher server and up
to eight Subscriber servers. Each server in the UCM cluster has a unique configuration.
A Cisco Unified Presence (CUPS) server cluster can support up to six servers. CUPS is server software that
centralizes network traffic from several different communications services so that it can all be transmitted over
the same Cisco Voice over IP (VoIP) network. CUPS uses industrystandard Jabber XCP for communication
between different instant messaging (IM) clients? Extensible Message and Presence Protocol (XMPP) is the
protocol that establishes the IM sessions. In addition, Jabber XCP facilitates other features such as file and
application sharing and video conferencing.

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