Vrrp Operation

Alteon OS Application Guide

Only the virtual router master responds to ARP requests. Therefore, the upstream routers only forward packets destined to the master. The master also responds to ICMP ping requests. The backup does not forward any traffic, nor does it respond to ARP requests.

If the master is not available, the backup becomes the master and takes over responsibility for packet forwarding and responding to ARP requests.

Selecting the Master VRRP Router

Each VRRP router is configured with a priority between 1–254. A bidding process determines which VRRP router is or becomes the master—the VRRP router with the highest priority.

The master periodically sends advertisements to an IP multicast address. As long as the back- ups receive these advertisements, they remain in the backup state. If a backup does not receive an advertisement for three advertisement intervals, it initiates a bidding process to determine which VRRP router has the highest priority and takes over as master.

If, at any time, a backup determines that it has higher priority than the current master does, it can preempt the master and become the master itself, unless configured not to do so. In pre- emption, the backup assumes the role of master and begins to send its own advertisements. The current master sees that the backup has higher priority and will stop functioning as the master.

A backup router can stop receiving advertisements for one of two reasons—the master can be down, or all communications links between the master and the backup can be down. If the master has failed, it is clearly desirable for the backup (or one of the backups, if there is more than one) to become the master.

NOTE – If the master is healthy but communication between the master and the backup has failed, there will then be two masters within the virtual router. To prevent this from happening, config- ure redundant links to be used between the switches that form a virtual router.

226 Chapter 13: High Availability

42C4911, January 2007

42C4911 specifications

Nortel Networks 42C4911 is a key hardware component designed to meet the needs of modern telecommunications infrastructure. As part of Nortel's extensive portfolio, the 42C4911 has made a significant impact on network design and operation, particularly in enterprises requiring reliable and efficient communication solutions.

One of the standout features of the 42C4911 is its modularity. This allows for flexible configurations and upgrades, enabling organizations to adapt to changing technology requirements and business demands. The design philosophy behind the 42C4911 emphasizes scalability, allowing users to start with a basic setup and expand it as their networking needs grow. This feature is particularly appealing to medium and large enterprises that anticipate increased data and communication requirements over time.

In terms of technology, the 42C4911 supports various telecommunications standards, making it versatile for multiple applications. It typically integrates with other Nortel equipment and can work with third-party devices, ensuring seamless interoperability across different platforms. This is critical as organizations look to create unified communications systems that can handle voice, data, and video traffic efficiently.

The 42C4911 is known for its robust performance and reliability. It is designed to operate continuously under demanding conditions, which is essential for organizations that rely on constant connectivity for their operations. Its built-in redundancy features help safeguard against potential failures, thus enhancing the overall stability of the network. This reliability is further complemented by Nortel's commitment to high-quality manufacturing standards, ensuring that users receive a durable and efficient product.

Security is another major consideration for any networking device, and the 42C4911 provides advanced security features to protect sensitive data. With increasing cybersecurity threats, organizations prioritize devices that offer strong encryption and access control mechanisms. The 42C4911 addresses these needs while facilitating secure communication channels for users, which is essential in today's increasingly interconnected world.

Overall, the Nortel Networks 42C4911 stands out as a versatile and powerful component in the telecommunications landscape. Its modular design, compatibility with diverse technologies, reliability, and emphasis on security make it an appealing choice for organizations looking to enhance their networks. As companies continue to navigate the complexities of communication, devices like the 42C4911 play a crucial role in ensuring that they remain connected and efficient.

Nortel Networks 42C4911 manual Vrrp Operation, Selecting the Master Vrrp Router

Models: 42C4911

Alteon OS Application Guide

VRRP Operation

Selecting the Master VRRP Router

42C4911, January 2007

42C4911 specifications