Cisco TelePresence Administrator's Manual page 242

Applications
VCS neighbors: if you have a deployment with two or more VCSs neighbored together, you are
n
recommended to enable only one presence server per domain. This will ensure a central source of
information for all presentities in your network.
VCS clusters: for information about how Presence works within a cluster, see
n
[p.167].
Note: any defined transforms
Presence Services.
Cisco VCS Administrator Guide (X8.1.1)
also apply to any Publication, Subscription or Notify URIs handled by the
Presence
Clustering and Presence
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