Polycom 3725-76302-001O Manual De Usuario

 Polycom

®

 RealPresence DMA

®

7000 System Overview

Polycom, Inc. 

19

● Ability to ping the other server’s public physical address 
● Ability to ping the default gateway 

In the event of a tie, the server already hosting the public virtual address wins. 

Failover to the backup server takes about five seconds in the event of a graceful shutdown and about twenty 
seconds in the event of a power loss or other failure. In the event of a single server failure, two things 
happen: 

● All calls that are being routed through the failed server are terminated (including SIP calls, VMR calls, 

and routed mode H.323 calls). These users simply need to redial the same number, and they’re 

placed back into conference or reconnected to the point-to-point call they were in. The standby server 

takes over the virtual signaling address, so existing registrations and new calls are unaffected. 

● Direct mode H.323 point-to-point calls are not dropped, but the bandwidth management system loses 

track of them. This could result in overuse of the available network bandwidth. 

● If the failed server is the active web host for the system management interface, the active user 

interface sessions end, the web host address automatically migrates to the remaining server, and it 

becomes the active web host. Administrative users can then log back into the system at the same 

URL. The system can always be administered via the same address, regardless of which server is 

the web host. 

The internal databases within each Polycom RealPresence DMA system server are fully replicated to the 
other server in the cluster. If a catastrophic failure of one of the database engines occurs, the system 
automatically switches itself over to use the database on the other server. 

The Polycom RealPresence DMA system is also available in a single-server configuration. This 
configuration offers all the advantages of the Polycom RealPresence DMA system except the redundancy 
and fault tolerance at a lower price. It can be upgraded to a two-server cluster at any time. 

This manual generally assumes a redundant two-server cluster. Where there are significant differences 
between the two configurations, those are spelled out. 

To provide geographic redundancy and better network traffic management, up to five geographically 
distributed Polycom RealPresence DMA system clusters (two-server or single-server) can be integrated into 
a supercluster. All five clusters can be Call Servers (function as gatekeeper, SIP proxy, SIP registrar, and 
gateway). Up to three can be designated as Conference Managers (manage an MCU resource pool to host 
conference rooms). 

The superclustered Polycom RealPresence DMA systems can be centrally administered and share a 
common data store. Each cluster maintains a local copy of the data store, and changes are replicated to all 
the clusters. Most system configuration is supercluster-wide. The exceptions are cluster-specific or 
server-specific items like network settings and time settings.