D 14049.01
07.2007 58
D 14049.01
07.2007 58
Introduction Getting
Started
System
Overview
System
Configuration
H.323 & SIP
Configuration
Registration
Control
Zones and
Neighbors
Call
Processing
Firewall
Traversal
Bandwidth
Control Maintenance Appe ndices
Zones and
Neighbors
The purpose of an Alternate is to pr ovide extra
reliability.
Each VCS can be part of a pool of up t o 6
Alternate VCSs that act as backu ps to each
other in case one becomes unava ilable (for
example, due to a network or power ou tage).
All the Alternates in a pool are con figured
similarly and share responsibili ty for their
endpoint community. When an end point
registers with the VCS, it is given t he
IP addresses of all the VCS’s Alternates. I f
the endpoint loses contact w ith the initial
VCS, it will seek to register with one of t he
Alternates. This may result in your e ndpoint
community’s registrations be ing spread over
all the Alternates.
When the VCS receives a Locatio n Request,
if it cannot respond from its ow n registration
database, it will query all of its A lternates
before responding. This allows t he pool
of endpoints to be treated as if they w ere
registered with a single VCS.
About Alternates
Each VCS can be configured wit h the IP
addresses of up to five other VCSs t hat will
act as Alternates should the cur rent VCS
become unavailable.
To configure Alternate VCSs:
VCS Configuration > Alternates.
You will be taken to the Alternates page.
xConfiguration Alternates
•
•

Alternate 1 to Alternate 5 IP addres s

To configure another VCS as an Alterna te, enter its IP address.
Up to 5 Alternates may be configure d.
Save
Click Save to save your
changes.
Configuring Alternates
Alternates are not used to increa se
the capacity of your networ k; they are
to provide redundancy. To increase
the capacity of your networ k, add one or more
additional VCSs and neighbo r them together.
Alternates are periodicall y interrogated
to ensure that they are still
functioning. In order to preve nt delays
during call setup, any non-fun ctioning
Alternates will not receive Loc ation Requests.
!
You must configure all Alternates in a
pool identically for all regist ration and
call features such as authentic ation,
bandwidth control and poli cy. If you do not do
this, endpoint behavior will var y unpredictably
depending on which Alterna te it is currently
registered with. Alternates s hould also be
deployed on the same LAN as ea ch other so
that they may be configured wit h the same
routing information such as lo cal domain
names and local domain subnet m asks.
When configuring your VCS wit h the
details of the system it will be using as
a traversal server, you are given t he
opportunity to include d etails of any Alternates
of that traversal server. Addin g this
information to your VCS will ensure th at, if the
original traversal serv er becomes unavailable,
your VCS can use one of its Alternat es
instead.
TANDBERG VIDEO COMMUNICATION SERVER
ADMINISTRATOR GUIDE
Managing Zones, Neighbors and Alternates