TANDBERG D14049.01 manual About Alternates Configuring Alternates, XConfiguration Alternates

Managing Zones, Neighbors and Alternates

TANDBERG VIDEO COMMUNICATION SERVER ADMINISTRATOR GUIDE

About Alternates Configuring Alternates

The purpose of an Alternate is to provide extra reliability.

Each VCS can be part of a pool of up to 6 Alternate VCSs that act as backups to each other in case one becomes unavailable (for example, due to a network or power outage).

All the Alternates in a pool are configured similarly and share responsibility for their endpoint community. When an endpoint registers with the VCS, it is given the

IP addresses of all the VCS’s Alternates. If the endpoint loses contact with the initial VCS, it will seek to register with one of the Alternates. This may result in your endpoint community’s registrations being spread over all the Alternates.

When the VCS receives a Location Request, if it cannot respond from its own registration database, it will query all of its Alternates before responding. This allows the pool

of endpoints to be treated as if they were registered with a single VCS.

Alternates are periodically interrogated

to ensure that they are still functioning. In order to prevent delays

during call setup, any non-functioning Alternates will not receive Location Requests.

Alternates are not used to increase

the capacity of your network; they are to provide redundancy. To increase

the capacity of your network, add one or more additional VCSs and neighbor them together.

Getting System

Introduction Started Overview

Each VCS can be configured with the IP addresses of up to five other VCSs that will act as Alternates should the current VCS become unavailable.

To configure Alternate VCSs:

•VCS Configuration > Alternates.

You will be taken to the Alternates page.

•xConfiguration Alternates

!You must configure all Alternates in a pool identically for all registration and

call features such as authentication, bandwidth control and policy. If you do not do this, endpoint behavior will vary unpredictably depending on which Alternate it is currently registered with. Alternates should also be deployed on the same LAN as each other so that they may be configured with the same routing information such as local domain names and local domain subnet masks.

When configuring your VCS with the

details of the system it will be using as

a traversal server, you are given the opportunity to include details of any Alternates of that traversal server. Adding this information to your VCS will ensure that, if the original traversal server becomes unavailable, your VCS can use one of its Alternates instead.

System	H.323 & SIP	Registration
Configuration	Configuration	Control

Save

Click Save to save your changes.

Zones and	Call
Neighbors	Processing

Alternate 1 to Alternate 5 IP address

To configure another VCS as an Alternate, enter its IP address. Up to 5 Alternates may be configured.

Firewall	Bandwidth	Maintenance	Appendices
Traversal	Control

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