Arp Behavior With Vrrp-E; Comparison Of Vrrp And Vrrp-E; Vrrp - Brocade Communications Systems FastIron SX 800 Configuration Manual

• VRID's MAC address
– VRRP uses the source MAC address as a virtual MAC address defined as 00-00-5E-00-01--vrid , where vrid is the
VRID. The Master owns the virtual MAC address.
– VRRP-E uses the MAC address of the interface as the source MAC address. The MAC address is hash-value-vrid , where
hash-value is a two-octet hashed value for the IP address and vrid is the VRID.
• Hello packets
– VRRP sends Hello messages to IP Multicast address 224.0.0.18.
– VRRP-E uses UDP to send Hello messages in IP multicast messages. The Hello packets use the MAC address of the
interface and the IP address as the source addresses. The destination MAC address is 01-00-5E-00-00-02, and the
destination IP address is 224.0.0.2 (the well-known IP multicast address for "all routers"). Both the source and destination
UDP port number is 8888. VRRP-E messages are encapsulated in the data portion of the packet.
• Track ports and track priority
– VRRP changes the priority of the VRID to the track priority, which typically is lower than the VRID priority and lower than
the VRID priorities configured on the Backup routers. For example, if the VRRP interface priority is 100 and a tracked
interface with track priority 20 goes down, the software changes the VRRP interface priority to 20.
– VRRP-E reduces the priority of a VRRP-E interface by the amount of a tracked interface priority if the tracked interface link
goes down. For example, if the VRRP-E interface priority is 200 and a tracked interface with track priority 20 goes down,
the software changes the VRRP-E interface priority to 180. If another tracked interface goes down, the software reduces
the VRID priority again, by the amount of the tracked interface track priority.
• VRRP-E can use HMAC-MD5-96 for authenticating VRRP-E packets. VRRP can use only simple passwords.

ARP behavior with VRRP-E

In the VRRP-E implementation, the source MAC address of the gratuitous Address Resolution Protocol (ARP) request sent by the
VRRP-E Master router is the VRRP-E virtual MAC address. When the router (either the Master or Backup router) sends an ARP request
or reply packet, the sender's MAC address becomes the MAC address of the interface on the router. When an ARP request packet for
the virtual router IP address is received by the Backup router, it is forwarded to the Master router to resolve the ARP request. Only the
Master router answers the ARP request for the virtual router IP address.

Comparison of VRRP and VRRP-E

This section compares router redundancy protocols.

VRRP

VRRP is a standards-based protocol, described in RFC 2338. The Brocade implementation of VRRP contains the features in RFC
2338. The Brocade implementation also provides the following additional features:
• Track ports - A Brocade feature that enables you to diagnose the health of all the Layer 3 switch ports used by the backed-up
VRID, instead of only the port connected to the client subnet.
• Suppression of RIP advertisements on Backup routers for the backed-up interface - You can enable the Layer 3 switches to
advertise only the path to the Master router for the backed-up interface. Normally, a VRRP Backup router includes route
information for the interface it is backing up in RIP advertisements.
Brocade Layer 3 switches configured for VRRP can interoperate with third-party routers using VRRP.
FastIron Ethernet Switch Layer 3 Routing
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