126 CHAPTER 8: MANAGING UNINTERRUPTIBLE POWER SUPPLIES
Set up two UPS devices to service a single VCX server with redundant
power supplies.
Set up one UPS to service multiple VCX servers.
Set up two UPS devices to service multiple VCX servers through one
server with redundant power supplies.
As a general rule, the power requirements of devices serviced by a UPS
should not exceed 80% of UPS load capacity. 3Com Corporation
recommends that you consult with you UPS vendor or reseller for sizing
assistance.
When UPS support includes multiple VCX servers, one VCX server is
designated the master. The master server acts as the coordinator for the
other VCX servers, referred to as slaves. The master communicates with
the UPS; the slaves communicate the master to get UPS status. If power
requirements call for more than one UPS, the VCX system may include
more than one master server. Note that the master/slave designation is
entirely independent of any role (primary, secondary, or branch) that a
VCX server may have within the VCX environment.
As described in VCX Software Components, VCX software can be
installed on VCX servers in many different configurations. When selecting
a VCX server to act as a master, follow these guidelines:
Choose a server that is running the VCX Authentication and Directory
service (preferred) or the IP Messaging service. The Authentication and
Directory service can run on any of the following VCX servers (see
Tabl e 3):
IP Telephony and IP Messaging Server
IP Telephony Server
Authentication and Directory Server
The master can be either the primary or the secondary server.
For example, your VCX system includes a region with an IP Messaging
Server, an Authentication and Directory Server, a Call Server, and a Call
Records Server, and the servers share a UPS. In this case, select the
Authentication and Directory Server as the master. However, if your VCX
system includes a UPS-powered Call Server and IP Messaging Server,
select the IP Messaging Server as the master.