General Features; Redundancy; Additional Redundancy Schemes; Policy - Quality Of Service (Qos) - Avaya P333R-LB User Manual

General Features

Redundancy

Routing protocols naturally provide some level of redundancy. However, IP
stations that are manually configured with a single 'default gateway' IP address do
not naturally recover when their default gateway fails. These stations do not
automatically try to use other routers or Layer-3-switches connected to the same
subnet.
The P333R-LB supports two types of router redundancy protocols, VRRP and SRRP,
to solve this problem. In addition, the VRRP solves the problem of VIP interfaces in
Server Load Balancing.
For full information, see VRRP on page 243 and SRRP on page 254.

Additional Redundancy Schemes

Using the P333R-LB, you can configure a Real Server to backup one or more
primary Real Servers. A backup Real server is not used until the primary Real
Server is down.
You can also configure a Real Server Group (RSG) to backup one or more primary
RSGs. A backup RSG can run a different service than the primary RSG while
providing backup to all of the primary RSG's services. Similar to the Real Server, the
backup RSG is not used until all Real Servers in the RSG are down.
For full information, see Additional Redundancy Schemes on page 258.
Policy – Quality of Service (QoS)
The P333R-LB supports QoS by using multiple priority levels and IEEE 802.1p
priority tagging to ensure that data and voice receive the necessary levels of service.
The P333R-LB can enforce policy on routed packets (per packet), according to four
criteria:
• The IEEE 802.1p priority tag in the incoming packet.
• The Diff-Serv byte (TOS field) in the IP header of the incoming packet.
• Matching the packet's source or destination IP address to the configured
priority policy.
• Whether the packet source or destination TCP/UDP port number falls within a
pre-defined range.
Since the P333R-LB is a multilayer switch, it can enforce centralized network
policies using Avaya's RealNet Rules central policy management application.
For full information, see Policy – Quality of Service (QoS) on page 265.
Avaya P333R-LB User's Guide
Chapter 1 Overview
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