Chapter 14 Load Balancing in the P333R-LB

Client persistency is achieved either by using naturally persistent load balancing schemes (such as Hash or MinMiss Hash), or by forcing persistent load balancing decisions on non-persistent load balancing schemes (such as Round Robin).

Decision forcing is performed by storing the history of the latest decisions in a cache for a limited time, and sending the packets to the appropriate server based on previous load balancing decisions.

Regardless of the client persistency nature of the selected load balancing metric, the P333R-LB offers a unique client persistency feature that is available in all load balancing metrics. Client persistency is based on a "persistency cache". Load balancing decisions are recorded in a persistency cache for a specified time configured by the user. When a new session that matches an entry in the persistency cache is processed by the P333R-LB, it is directed to the same server pointed by the cache (provided, of course, that the server is considered healthy).

The key to the persistency cache is based on the client IP, in combination with a wildcard. This allows persistency to be configured per an exact IP address, or per a group of addresses. For instance, in cases where clients hide behind a NAT device which selects NAT addresses from an address block of 255 addresses, enabling the persistency cache with a wildcard of 0.0.0.255 will map all clients to a single entry and a single Real Server.

Selecting a Load Balancing Metric and Persistency Option

The different load balancing metrics and persistency options provide you with flexibility.

Round Robin generally gives you the best load balancing solution.

Hash, with the key set to Src IP, gives a predictable metric, required when client persistency is needed and a redundant load balancer is used.

MinMiss Hash, with the key set to Src IP, gives the best persistency, without using the persistency cache.

The persistency cache mechanism enables you to specify the required client persistency time.

The wildcard feature allows the client to maintain persistency when the same client is mapped to a different IP address by a NAT device. However, persistency cache size is limited, and it somewhat increases the session processing overhead.

Port Re-mapping

The P333R-LB may be configured to re-map the destination port number when performing load balancing. For example, you might want to run the HTTP process on real servers using a different port number in order to enable more than one concurrent HTTP service.

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Avaya P333R-LB manual Selecting a Load Balancing Metric and Persistency Option, Port Re-mapping
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P333R-LB specifications

The Avaya P333R-LB is a robust and versatile switch that is part of Avaya's portfolio aimed at enterprise networking solutions. This switch is designed to enhance the performance and scalability of network infrastructure while ensuring high availability and reliability.

One of the main features of the P333R-LB is its Layer 3 switching capability, which allows for efficient routing within an organization's network. This capability is particularly beneficial for organizations with multiple VLANs, as it simplifies the routing process and ensures that data packets are transmitted in the most efficient manner possible.

The P333R-LB is equipped with advanced Quality of Service (QoS) features to prioritize traffic based on the type of application being used. This ensures that critical applications, such as VoIP and video conferencing, receive the necessary bandwidth and low latency required for optimal performance. Additionally, it supports both IPv4 and IPv6 protocols, making it adaptable to a variety of networking environments.

Another important feature of the Avaya P333R-LB is its stackable design. This allows multiple switches to be interconnected, creating a single logical unit. This stacking capability not only simplifies management but also increases overall network capacity and redundancy. In case of a hardware failure, the stack can continue operating without interruption, maintaining network integrity and service continuity.

The switch also integrates advanced security features, including support for MAC filtering, access control lists, and port security. These features help to safeguard network resources from unauthorized access and potential threats. Moreover, the P333R-LB supports 802.1X port-based authentication, which adds an additional layer of security during user access to the network.

The Avaya P333R-LB comes with multiple Gigabit Ethernet ports, allowing for high-speed connectivity to devices such as servers, workstations, and IP phones. This ensures that all devices on the network can communicate effectively, supporting the demands of modern enterprise environments.

For management and monitoring, the P333R-LB offers a user-friendly web interface along with SNMP support, enabling network administrators to easily configure settings and monitor network performance. This simplicity in management is crucial for IT teams that need to ensure optimal network performance while minimizing downtime.

In summary, the Avaya P333R-LB is a feature-rich, scalable, and reliable switch that meets the needs of demanding enterprise networks. With its advanced technologies, QoS support, stackable design, robust security features, and high-speed connectivity options, the P333R-LB is positioned to support a wide range of applications and enhance overall network performance.
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