The following guidelines apply to using VRRP (Virtual Router Redundancy Protocol):
VRRP packets are encapsulated IP packets.
The VRRP IPv4 multicast address is 224.0.0.18.
The VRRP IPv6 multicast address is ff02::12.
The maximum number of supported VRIDs per interface is 255 for V3-v2 version mode, and 255 for v2 or v# version mode.
An interconnect link between VRRP routers should not be used, except when VRRP routers have hosts directly attached.
VRRP instance scale is dependent on platform and license. Please refer to the ExtremeXOS release notes for details.
Up to 255 unique VRIDs can be configured on the router.
VRRP and other L2 redundancy protocols can be simultaneously enabled on the same switch.
When VRRP and BOOTP/DHCP (Dynamic Host Configuration Protocol) relay are both enabled on the switch, the relayed BOOTP agent IP address is the actual switch IP address, not the virtual IP address.
We do not recommend simultaneously enabling VRRP and ESRP (Extreme Standby Router Protocol) on the same switch.
VRRP and ESRP cannot be configured on the same VLAN (Virtual LAN) or port. This configuration is not allowed.
RFC 5798 describes a situation where a master VRRP router takes on a duplicate IP address due to interaction with the duplicate address detection (DAD) feature. To prevent such duplicate addresses, the DAD feature is disabled whenever a VRRP router is configured for IPv6 or IPv4.
A VRRP router instance can be configured with multiple IP addresses on the same subnet or on different subnets, provided that all virtual IP addresses match the subnet address of a VLAN on the switch. For example, if a host switch has VLAN IP addresses in the 1.1.1.x and 2.2.2.x subnets, then that VRRP router instance can contain virtual IP addresses in both those subnets as well.
If a VRRP router instance is assigned priority 255, then the host router must own all the IP addresses assigned to the VRRP router instance. That is, each virtual IP address must match an IP address configured for a VLAN on the router.
When a VRRPv2 instance spans routers using ExtremeXOS version 12.6 and earlier and routers using ExtremeXOS version 12.7 and later, routers using ExtremeXOS version 12.6 and earlier log packet-size warning messages.
Note
A maximum of 511 VRRP instances are allowed without One-To-Many Mirroring. If using OTM Mirroring, only 507 VRRP instances are allowed. You can increase VRRP scaling limit by using VRRP grouping (see VRRP Grouping to Increase VR Scaling).